- In China, Laurence notices many of the women walk with a "queer, mincing gait". He wouldn't know about foot binding, of course.
- In Throne of Jade, there's an amusing little subplot where Laurence hears about a nasty cold going around the English dragons, and many jokes are made about how dragons are such big babies when they're sick. Temeraire comes down with the cold, and it's played largely for laughs. In Empire of Ivory, it turns out that the "cold" is actually a form of dragon tuberculosis that's slowly and painfully killing every dragon in England, and if they hadn't stopped at exactly the right port in Africa and prepared exactly the right mushroom for Temeraire on a whim, he and every other English dragon would have died. And for that matter, since Temeraire was on his way to China, all of the Chinese dragons would probably have died, too.
- The period after Napoleon's fall in real life resulted in a massive conservative backlash that led to two World Wars and colonial empire's continued survival for over 150 years.
- There's a good reason why it makes sense that Napoleonic France would be in a position to extend equal rights to dragons, and it's not simply getting an advantage over England. One of the founding tenets of the Republic (and legacies of the French Revolution) is the motto "Liberty, Equality, Fraternity." What Napoleon did was in effect extend the same rights enshrined in that ideal to dragons, effectively making them just like any other citizen of France. Also, since dragons were considered demonic in at least some traditionalist lore, their vindicated place can be considered an ideological and systemic Take That against the old order.
- In Empire of Ivory, we learn that there is a thriving, very complex society in sub-Saharan Africa. While there were certainly smaller, less centralized empires in "real world" sub-Saharan Africa, they could never reach the level of complexity that similar societies did in Asia, Europe and the Americas. Why? Well, according to Jared Diamond in Gun, Germs and Steel, the scourge of malaria forced sub-Saharan Africans to live further from sources of water and in smaller, less densely-populated communities. In Throne of Jade, however, it's very casually mentioned that dragons naturally repel mosquitoes. Fridge Brilliance, indeed!
- The design of the dragon transport, specifically in its being strangely narrow for such a long ship (except for the wide dragondeck), is more or less a Wooden Ships and Iron Men take on an aircraft carrier.
- Temeraire and Laurence are symbolized by wind and water, respectively. These are the titular elements of Chinese feng shui- it's no wonder they work so well together!
- Hammond frequently takes ill at high altitudes. To alleviate this, he is given bundles of coca leaves as treatment; a common remedy in South America, even today. Over the next few books he continues to use them in comic excess. It seems rediculous, until you remember the more infamous application of coca leaf...