I've not done all of the eras, but broadly speaking, you've got a wide selection to choose from. I've neglected to include eras that were very close together; I'm afraid people looking to control Revolutionary France are going to be disappointed. American patriots will be pleased though.
(PS: If people really want to go Revolutionary France or one of its rivals, we can go it. Just request it instead of one of the eras. Not much changes from the American Revolutionary start bar France has a revolutionary government instead of a Monarchal one.)
France is at its weakest point, being split neatly in half by unreliable vassals, with England stubbornly holding onto Calais and Gascony in the South West, its powerful navy rendering it all but unassailable from its island stronghold and free to carry out operations on the continent and anywhere else for that matter. Castille and England are strongest, both having powerful navies and armies and both having easy conquests in the form of northern France and Burgundian Picardie for England and Granada and the pathetically weak North African nations for Castille. Portugal, Aragon and Burgundy are also all major powers, albeit weaker ones, and could all throw their hats into the ring for glory and power if they move fast enough. Castille must guard its status as defender of the faith carefully, or have it stolen from it. If any of these powers gain dominance, they will be almost free of constraints to suffocate the divided Holy Roman Empire and weaker Scandinavian and Italian states before they can emerge into powers of their own. Scotland looks for an opening, as Irelands four minor kingdoms, Tyrone, Munster, Leinster and Connacht, battle for control, ignoring the behemoth slumbering at their doorstep... or perhaps simply too scared to do anything about it.
Central Europe. Naples is the most powerful of the Italian factions, holding Southern Italy, but this isn't saying much given the fractious and divided state of affairs for the birthplace of Rome, and although they have a personal union with Provence, and thus, a foothold in France, France is not about to let this go uncontested, and weakened as they are, they still have plenty strength for settling this score. An alliance with England would not go ill-advised, and perhaps with Castille and Aragon, but beware being dragged into their own squabbles. Milan and Venice leave the north divided, and must settle their scores with each other before any hope of Italian unity can be dreamt of. Nonetheless, foreign nations are, for the moment, outside of Italy, and this state of affairs is something the Italians would do well to maintain.
The Holy Roman Empire is weak. It is not a true nation, but rather, made up of dozens of tiny, fractured nations, none of whom are prepared to stand fast in case of an attack and half of whom are as likely to war with each other as the two nations actually capable of mounting effective resistance, Austria and Bohemia, are rivals for control of the forsaken country. Threats are everywhere. The French and Burgundians keep each other distracted for now but they are still mighty threats and even now could threaten to wrestle imperial lands from the hands of the Emperor, be he Bohemian or Austrian. Hungary and Poland are distracted with the Ottomans and the Mongol hordes respectively, but should they waver in this duty and turn their eyes westward for expansion rather than allies, the hope of the empire may be silenced; the Germanic states cannot survive without their strongest members for long. If the empire cannot get its act together, it faces ruin as it is crushed as the east and west move towards one another.
The Scandinavians, for the moment, stand united under Denmark in a personal union, but things are unlikely to remain this way for Sweden, which is quite capable of looking after itself, or even swallowing its temporary master. For all the wisdom in Scandinavian unity, the Swedish and Norwegians see themselves as equal kingdoms to the Danes, and see little reason why they should be the ones to submit, not when Sweden is quite capable of smashing both its neighbours in battle both at sea and on land. But the Swedes fail to see the larger picture. If France cannot contain England, or the English unify the British Isles, Norway will seem like a delicious target. The Holy Roman Empire may not remain divided forever. And the Golden Hordes advance is seemingly endless. With these threats coming from all corners, the Scandinavian powers can ill-afford to squabble over who is greatest amongst the weak, and either by force or friendship, they must put aside their differences and come to some accord if they are to avoid facing a fight for survival in the future.
Eastern Europe and the Balkans
Lithuania and Poland fight for their very survival in union with one another as the Golden Horde presses relentlessly into Europe, threatening to bring Eastern Europe under the Khans authority. The Lithuanians and Poles were enemies not so long ago, and it is a tenuous union as the Lithuanians are much more powerful than their Polish overlords and have seen off both the cause and the power behind the Teutonic advance. For the Teutonic part in all this, perhaps it is time to accept that the old conflict with Lithuania is pointless in this new era? Rather than continue to fall into weakness, greed and hypocrisy in the face of this new threat, is it not time for this old monastic order of crusaders to join with the Lithuanian converts, and strike this new Mongol threat from the face of the world? The Teutonic order has committed terrible, horrific atrocities, and many would see their latest reversals in the face of Lithuanian and Polish might as just deserts for their actions. Perhaps, with their redemption, can come renewed glory, and honour in the cause of eastern crusaders can be restored.
Meanwhile, the Byzantines are in trouble. They have been reduced to the tip of the Peleponnesus and their once-proud capital, Byzantium. The cause of this, the Turks, are no longer separated by the Sea of Marmara. Their mighty armies have free reign in Europe, and are subjugating many of the Balkan states, the latest victims of which have been the once fiercely independent Serbians and Bosnians, who now meekly submit to the power of the Ottoman Sultan. Relief, perhaps, could come from the Hungarians, but just how much can be hoped for from these descendents of the Huns? The Hungarians have shielded the Byzantines from the north for long, but even if this shield has stayed true in the north, and still does so against the terrifying Mongols, can it truly reverse the Ottoman threat? If not, the Byzantines have to accept that their hope for survival does not lie in its now pathetic army. It lies in its still considerable wealth, and the new great ships that the Ottomans still lack. If the Ottomans could be trapped in Asia Minor by their concerns in the east, and Europe snatched back, surely the Byzantines could then turn their attentions to vengeance over the greedy Venetians, and even dream of reviving what many Romans have lost hope of; the recapture of Asia Minor itself. But the Ottomans are not the only concern, and Byzantium would do well to keep the pope onside... and consider if the Ottomans are truly the worst threat out there...
The mighty Timurid menace, stretching out of Central Asia, threatens to overwhelm the otherwise mighty but overshadowed Ottoman and Egyptian Mamluk nations as the spectre of crusade and the decadent and declined but still present shadow of Rome lingers. The Ottomans may need to put aside differences with their Orthodox foes in order to present a credible resistance to this new hazard, particularly their Georgian neighbours straddling their northern border, but they would do well to fear a Byzantine navy or a Hungarian counter-attack. The presence of the still powerful Qara Koyunlu to the east, and Jalayirids to the south, shield the Ottomans and Mamluks from the worst, but if they fall, little will stop Timur from claiming everything else. The Arabian peninsula is hopelessly divided and will provide no help, but perhaps it can be absorbed? With the armies of Islam so divided, can anything stop this terrifying steppe advance? Is this the end of the old Sultanates?
Novgorod taciturnly stands guard over its weaker neighbours and grimly watches events unfold in eastern Europe. It has been bested by the horde once before. This may now be the time to put aside old grudges with the papist rats to the east. It may be distasteful to deal with heretics, but with the whole of Christendom under attack from two fronts, surely now, if ever, is a time to heal the ancient scars, and join forces with those who were once despised.
If not, the old foe may be swept away by the new... and Novgorod, mighty and wealthy as it is, can only expect annihilation as reward for its pride...
Central Asia and India.
The Timurids and Golden Hord crush the steppe nations of Kazakh and Nogai between them as the strong north Indian nations of Delhi and Rajputana squabble with each other and weaker nations just as their ancestors did when Alexander happened upon them. In southern India Deccan and Vijayanagar are dominant, but Drissa, Bengal and Bihar may seek to change the balance of power. All would do well to fear the Timurids, and once Timur is finished in the west, what is to stop him from turning his armies around and sinking the his fangs into India, like a greedy, bloated wolf, happening upon a weak, defenceless and distracted cow, separated from its calves?
China and the East.
The Ming dominate 2/3rds of modern day China as the Manchu and Tibet stand as weaker rivals in its north and west respectively. With this juggernaut standing right at their doorstep, Korea and Japan eye each other, one with fear, the other with arrogant disdain, and greedy eyes. But is Japan missing the true enemy? The South-eastern powers are scattered, with none likely to prove much difficulty to a Ming commander, but if they could ever unite... in Indonesia to the south, the islands of Brunei, Aceh, and Mujapahit are free from dangers, and may battle for dominance... for the moment. One would not advise them to take too long settling this affair...
Most of this place is controlled by small, insignificant tribes, but a few potential nations exist here. The 5 great tribes of the east, the Huron, Iroquois, Shawnee, Cherokee and Creek, running from north to south, stand proud and ready to vie for dominance over the American east coast. But can anything they do possibly prepare them for the inevitable European onslaught that is to come?
The Aztecs fend off the much stronger Zapotec empire to the south and fight for breathing space, as the Maya watch on nervously from south of them. Will they intervene in the matter?
Nothing but the tiny Inca nation and the soon to be devoured Chimu within them to report. That won't change for a while, so grab a few drinks while you wait for anything significant to occur. At least there is a distinct lack of enemies in this part of the world.
Morocco and Algiers stand guard over Granada and dare Castille to complete the Reconquista. Algiers, however, may be vulnerable to being distracted by the Tunisians and Tripolitanians to the east, so Morocco may have to prepare to take the might of Castille on alone, a task they are sorely underprepared for. Sicily looks for an opening.
The Mali, on the south-western coast, look ready to annex the weak Ashanti to the south of them, and then, move onto the Songhai, and there is little chance of anyone stopping them. Towards the interior the Hausa and Kanem Bornu stand ready to fight for dominance. But the Hausa heartland is on the coast, and the small state of Benin is threatened by the larger Oyo. If the Oyo can secure Benin, what may become of the Hausa capital, separated from its interior possessions as it is by hostile tribes?
Ethiopia guards the way south for Mamluk Egypt as the Swahilis further south guard an extended coastal kingdom against Adal, and the infidel Mutapa. Perhaps it is here, this close to Arabia, that an African power is most likely to emerge?
Overall; The Mongol and Timurid hordes are the greatest threat to everyone at this point, but no one nation is dominant and any of the major powers of the time, and even a few minor ones, could potentially triumph. Even France and Ottoman Turkey are vulnerable. England and Castille are dominant in Western Europe, but that could easily change. The Ming are seemingly unassailable in the East... seemingly. This is also the biggest chance for an African nation to seize the initiative and come to power before those bastard Europeans start arriving in force.
1453: Fall of Byzantium
France manages to absorb some of its vassals and now emerges as a credible and triumphant challenge to England, which has fallen back to Calais before it loses everything. Scotland still stands upon the sidelines of the war, looking for any sign of weakness. Granada clings to life as Portugal manages to get a foothold in Morocco ahead of Castille. Aragon claims Sicily, and is not far away from digging its claws deeper into the Italian interior.
Things are looking grim indeed for any powers in the centre that wish to grow. Venice and Milan war with each other, exposing Venices Balkan possessions, and though Venice has managed to claim some Dalmatian lands on the Balkan coast at Hungarys expense, there is little question of it standing for long against the might of Ottoman Turkey. Aragon has its claws in Sardinia and Sicily and Naples looks to follow suit. Central Italy is as divided and chaotic as ever. Sweden has broken away from Denmark and seeks to fight their old leading partner as Norway sits on the sidelines twiddling its thumbs. With the Netherlands in Burgundian hands, it falls to a growing Austria to be the empires shield in troubled times. At least the Hungarians have allied with them. But how long can this state of affairs persist?
Bosnia and Serbia make an ill-timed break for independence just as the Ottomans finish their old Byzantine foes. Now only Morea remains. Only Hungary could possibly come to their aid, but will the Austrians aid them in this? And can either nation really stand against an Ottoman steamroller? Lithuania is spared the Golden Horde as the Crimea breaks away from them, but can this new Islamic Sultanate really be trusted to act as Europes shield? Lithuania also presses up against the Teutonic order. Poland manages to steal a fragment of its junior partners lands in the process.
The Middle East.
The Arabian Peninsula is as divided as ever, but the Ottomans batter their way west and the Mamluks east. East of them, the Qura Koyunlu stand as a new Shiite empire, while the Timurids retreat to Central Asia, a mere shadow hopefully never to be seen or heard of again. Georgia, to the Orthodox worlds relief and Ottoman Turkeys chagrin, still survives.
As the Horde breaks up into a mere shadow, the new Khaganates of Crimea, Kazakh and Siber, stretching from west to east, are now on the defensive, standing against Novgorod and its smaller orthodox neighbours. Crimea, at least, would also do well to beware of Lithuania...
Central Asia and India.
India has changed little, but where the almighty Timurids once threatened all, now they stand as humbled equals in the centre of four new powers, Nogai to the north-west, Kazakh to the north, and the sultanate of Khorasan to the south. The Chagatai are north-east of Kazakh, but are unlikely to pose much threat to these powers. They could, however, compete for Indian lands should the spark of conquest be restored to the steppe peoples. Can these new states live in peace? More importantly, can they resist the advance of the Qura Koyunlu east?
The rest of the world has either not changed, or any changes have been marginal.
Overall: Byzantium has fallen, and the Ottomans are ready to sweep all aside. France has stabilised and Burgundy is growing, and now it is England who is vulnerable. The same cannot be said for Castille. Things go from bad to worse for North Africa and Central Europe, particularly Scandinavia, which has fractured.
1492: A New World!
While Columbus is away doing his thing, spreading disease and future misery amongst the occupants of the new world, France and Austria decide that their needs outweigh their differences and split Burgundy between them. If the Burgundians had any objections to this, their voice clearly wasn't given much weight; they are gone. France is now dominant here in the north, to Englands woe, as Castille and Aragon gang up on Granada and Castille stands on the brink of annihilating the pesky emirate. Morocco, having ceded much of its west coast to Castille, has decided it isn't worth supporting the pesky state. Algiers agrees. Brittany is also under personal union with France, as France also eats up the majority of its vassals. England is now running scared, but, still at war with France, its clings stubbornly to Calais and won't let it go. Scotland and the Irish kingdoms watch nervously; they know their best opportunities are gone now. Scotland does at least manage to steal Orkney off of the Norwegians.
Austria has done it! The Burgundians are driven from the Netherlands and Austria takes its place as the true protectors of the empire. Some semblance of unity is emerging. Denmark has managed to get Sweden and Norway back under its thumb again, but France is the new threat, and the Aragonese still have their claws into Italy.
Eastern Europe and Western Russia
The Ottomans begin mop up of the few remaining Balkan states as Hungary braces itself. The Livonian Order breaks away from the Teutonic Knights as Poland begins to swallow them up, vassalising the once dominating order. Muscovy surprises everyone by taking over Novgorod. In the Khaganates, the last of the Golden horde almost disappears as the new Astrakhan khaganate emerges, but little else changes.
The Middle East.
The Ottomans seize Genoas Crimean provinces and much of the Balkans, and mostly consolidate Asia Minors few remaining minor kingdoms. Tempering them is the massive empire of Ak Koyunlu, stretching from Georgia to the Persian Gulf and from the immobile Mamluk border to the Central Asian states. The three check each other, as the Arabian peninsula remains stubbornly unchanged.
Central Asia and India.
Delhi begins to dominate, stretching across northern India, as the Timurids are cut into by the Chagatai to the east. The Deccan consolidate and become a credible source of unity and power in the south of India.
No changes in the East.
The Aztecs expand into tribal territories, the Inca expand into the South American north-west.
Portugal and Castille begin to chop up Morocco, and Portugal arrives off the coast of West Africa, claiming the island of Fernando Po, off the West African coast, as the Songhai push back and equalise with the Mali.
1579: 80 years war.
Western Europe and Empires.
France and Spain carve up Western Europe for themselves, Castille finally uniting Aragon under their banners along with most of Italy including all the islands of the western mediterranean, almost a Spanish lake. Adding to this is Spains almost total control of South and Central America... Portugal takes the eastern part of South America and stops the Spanish getting too proud. The once proud nations of Southern and Central America are now gone. Portugal finally lands on the western South African coast around Kongo, and arrives on the Indian Coast and the island of Ceylon (which really surprised the Ceylonnese)
Austria barely fights off the dominant Ottomans as it loses the Netherlands it fought so hard to seize to Spain. To make up for this loss it unites with Bohemia and a severely weakened Hungary. Denmark annexes Norway, but at a cost; Sweden is now hostile and seemingly permanently lost; it would take a tremendous struggle to unite Scandinavia now. Venice has lost most of its Balkan possessions, and with the Spanish nearly in control of Italy, can anyone save the peninsula from Spanish domination?
Eastern Europe, Russia, and the Steppe Kingdoms.
Russia gains some of Lithuania as Poland claims the rest. The Crimea is slowly being carved up by the new Russian nation and the Ottomans. Only a handful of states remain free of the Ottomans in the Balkans. Much of Russia has now formed, with only Kazakh and Siber grimly hanging on to life as major players. To the east the Mongols have regained some of their old life, but they are still vassals under the Ming. The Central Asian States have been replaced by Persia in the south, Kazakh in the north, and the weak Khaganates of Khira and Shaybarid in the centre. Can these nations possibly stand against the might of the Ottomans, now that they control the whole of the Middle East?
Not much to see here but the Ottomans, who have taken over the Mamluks and Hedjaz, and are now a superpower. Georgia is gone now, and the Arabian peninsula states barely cling to life. Much of Yemen is also in Ottoman hands.
The Mughals have emerged and this new Islamic power dominates the north. Islam has finally invaded the peninsula. In the south the Portuguese take Ceylon and part of Bijapur, and with the Deccan and Vijayanagar reduced in power or, in the latters case, annihilated, there is no unifying voice in the south. Things look bleak for those who cling to the olden ways...
China and the East
Little to report.
North and West Africa
The Ottomans have control of Tunisia and much of Algiers now. Tripoli is unaffected but surrounded by the new arrivals. Morocco has traded its north to Portugal and Spain for its west coast back, and makes up the difference by pushing into Africas interior, meeting up with the growing power of the Songhai, who have beaten back the Mali even further. Portugal has landed near Kongo in South Africa, and Loanga has emerged!
Portugal seizes Southern Swahili and Mutapan lands as Ethiopia retreats in the face of Ottoman might. The Funj, however, emerge just west of them in the interior. Perhaps these new peoples can beat back the invaders of East Africa... or will they turn into just another enemy?
Overall; Spain in the west, France in Europe and Ottomans in the east; this is a bad time to be any other European power. In fact, it is a bad time to by anyone other than those three powers... unless you're Chinese.
1701: War of the Spanish Succession.
Western Europe and Empires.
Spain, France, Portugal and a smattering of smaller nations battle England, Prussia, Austria, the Netherlands and Hannover and Lorraine (both smaller states) over who gets the French crown (i.e. nobody bar the French and Spanish want it to be a Frenchman, and especially not the French king.) Portugal expands its holdings in West and East Africa and, along with Spains expansion into the south of North America, its eastern South-American holdings too... but loses Ceylon to, of all people, the Dutch. The Dutch also land in Cape, as in Cape Town in South Africa, as Britain arrives in India and founds the 13 colonies in North America. It has also taken Ireland. Spain still controls half the low countries however, as the Netherlands battles for full control of its own territories. France is now fully formed, allied with Spain, and both are a true menace.
Sweden battles Russia, Poland and Saxony over a patch of dirt on the Baltic coast as Austria takes a well-deserved break from killing Ottomans to stave off France and her German and Spanish allies. It has taken back to the border with Bosnia in the Balkans, and has expanded its new Hungarian lands to include most of Transylvania. Prussa has emerged and, for now, fights alongside Austria, but can the peace last? However, even with these two powers and more powerful states emerging like Saxony and Bavaria, with the HRE slowly drifting towards unity, can this divided centre possibly hold against an almost united, fantastically wealthy west? What part will the newly strengthened Poland and Sweden, not to menton a gradually strengthening England, play in all this? This assumes the former two can hold against the terrifying power of Russia. Even as the Papal state achieves some kind of unity in central Italy, Venice is in full retreat as a power. Spains triumph in Italy seems all but assured, and it really would take Gods chosen appointee to turn the Hapsburg dynasty back now...
Eastern Europe and Russia.
Austria has held off the Ottoman threat, and Venice is back in the Peleponessus, but the Ottomans still hold most of the Balkans and are a terrible force to be reckoned with. Poland and Russia battle Sweden as Russia also deals with northern Rebels. The Crimea and the new Zaporozhie state have both clung on to life as vassals of the Ottomans and Russians respectively. Russia has finally destroyed the old steppe powers, and now has a border with China. Only Kazakh stands firm.
Middle East: No changes. Pax Ottomans reigns.
Central Asia and India.
The Islamic Mughals come close to Indian unification but face difficult resistance in the south and, more seriously but less immediately, the attention of three colonial powers; Britain, Portugal and the Netherlands. Kazakh grimly holds the line against Russia but weak Khira to the south-west threatens to give and open up a flank. Persia has stood fast against the Ottoman threat to the west. Both eye up Shaybarid, which is caught inbetweeen both... but the Mughals also border it, and this may drag either one into a battle in India.
The East and China.
China has finally unified... under the Manchu? Tibet and Korea tremble at this news as Japan stealthily extends its influence north into the islands surrounding it. Southeast Asia is as divided as ever. The Netherlands have arrived and taken most of Indonesia. Portugal is also in the area, on the island of Timor off Australias coast.
The North American Nations live in fear for their existance as France in the north, Britain in the east and Spain in the south vie for domination in this new world. In the south the Spanish and Portuguese run out of room to expand and eye the lands of the other up greedily, as the Netherlands and France land on the South American coast. Britain grabs a few islands. It has also secured parts of Canada.
North and West Africa
Algiers takes back its lands from the Ottomans as Morocco kicks out the Portuguese, but Spain refuses to go and even expands into the old Portugues possessions in the north. The Mali and Songhai suffer a collapse as the Mali somehow move north above the Songhai! Or, what is now the Segu. Who are engulfed in civil war. Oops. Portugal has Kongo on the ropes.
The Swahili and Mutapa near annihilation in the face of Portuguese and lately the Omani, who have both sliced up over 70% of their territories between them. Funj begins to dominate as Ethiopia collapses. Just off the coast, Yemen restores its borders with the Ottomans.
Overall: Things look slightly less grim for Britain and the Ottoman empires neighbours, but the world is still in dire straits. The Manchu now have the chance to make a serious bid for domination... just do it while the Europeans are distracted with each other, ok?
1776: American War of Independence.
Europe and Russia.
For the moment, things are peaceful. Great Britain has finally emerged. Austria has lost some ground to Prussia but it has fought the Ottomans even further south. Poland and Sweden, however, are buckling under Russias weight. Other than that, none of those big wars got anyone anywhere.
Central Asia and India.
As Britain begins to move into its east and west, Indias Mughal empire fractures into pieces, and Indias best hope for protection from these European invaders (ironically, by an invader) is gone. Persia is shoved west as the new state of Durrani emerges onto Indias border, and indeed parts of India. The Hindu Maharasthra emerge in India amongst the carnage, but can any force possibly stop the British now? However, rumbles from the west suggest that all is not lost. Someone is standing up to these people.
Little to report except the Ottomans suffering another blow as the Hedjaz kick them out.
East Asia and China.
Interesting news in South-east Asia as the Taunga and Ayutthaya begin to finally move towards unification. However, they still have one another to worry about. Not to mention, you know, the terrifying presence of Manchu China, the more insidious threat of the now thoroughly Dutch Indonesia, and the not-inconsiderable threat of Tibet, though it has its own fears. Even if they do manage the impossible, what power on earth could possibly threaten Manchu held China?
Great Britain has, apparently, made the rather large misstep of annoying the 13 colonies... into a full-scale revolt. The USA has arrived, and the battle for independence is on! But what will France and Spain do about it, particularly the still mighty Spanish? Britain now holds half of North America, Spain, just about everything else bar Portuguese South America, the French and Dutch possessions, and a number of British and French held islands. The world, it seems, would be hard pressed to stop either.
I seem to have forgotten about this part. Either that, or nothing much has changed.
Overall; Despite the obvious appeal of playing the emerging USA, there are a few interesting late game choices here. For example, the south-asian states, or perhaps one of the Indian powers? But the British and Spanish seem to have the greatest chance of actual success... assuming they can ever deal with each other. France still definitely has a role however, as it is about to demonstrate... the Ottomans are still a very real threat, but do not represent the same superpower as before.