This trope is when horses are portrayed as symbols of masculinity, potency, fecundity, and virility.
Ironically, wild horses are led by their oldest mare, who is the one to direct the herd's movements, guide it to food and water sources, and otherwise control its direction and routine. In reality, the herd's stallion has the primary role of breeding with the mares and defending the herd by fighting predators and rival males. This lionization of male horses led to the belief that stallions were the leaders of the herd through Darwinian rights, which led to the masculinization of horses in symbolism and cultural depictions.
Since horse riding and horse caring were once associated with nobility, horse ownership was once seen as a symbol of wealth. When ranchers in the Wild West rode horses as they rounded up cattle, it became associated with the manly art of tending the land and being self-reliant in their craft.
Due to their association with virility and masculinity, this trope is more associated with men than women since men have to be providers and are known to be more competitive against other men. Like horses, if a man is deemed too weak to work or too old to do their job then he'll be made redundant and therefore emasculated by the public for being weak and frail. Of course, this was before technological improvements, workplace health and safety regulations, and anti-prejudice laws were brought in to improve the workplace.
In a crude sense of symbolism, the association with sexuality is believed to be associated with a horse's genitals as they are famously well endowed, which correlates with the masculine insecurity about the size of their manhood. However, when horse-riding became associated with femininity, it's common for bulls to be associated with unbridled masculinity instead.
It can go with Cool Horse, Our Centaurs Are Different varies in application because they are mythological half-man, half-horse creatures. The original centaurs of Greek mythology, however, were very much subject to this trope. The rooster is another farm animal with similar connotations about masculinity and virility. Compare Alpha and Beta Wolves, a similar misunderstanding of animal "dominance" and group dynamics. Contrast All Girls Like Ponies for when horses are seen as feminine. Compare Diligent Draft Animal, where the draft horses' strength is emphasized in the context of work endurance rather than masculinity.
- Ranma ½: Ranma Saotome has the meaningful name "Wild Horse", has quite a lot of pride in his manliness (he's a top-notch martial artist) and any kind of questioning about it is a Berserk Button. Which of course makes it quite ironic that he has a curse that turns him into a woman and he comes to embrace it because it allows him to do things like eating ice cream without shame. It also turns out to be enforced because his father made an oath to his mother that Ranma would be a "man among men" courtesy of his martial arts training under threat of Seppuku if they failed.
- Mad Max: Fury Road: Immortan Joe has this as his motif. His gas mask is decorated with horse teeth, his car is named the Gigahorse, carries a pair of western-style revolvers of the type used by 19th-century cavalrymen, as well as his attempts to breed the perfect heir which bears a very uncomfortable similarity to equine husbandry.
- Rocky: Invoked, Rocky is called "The Italian Stallion" because of his Italian-American heritage. Rocky had to work hard to be a champion, he trains in a barn, and he returned to the ring in the 2006 film in order to prove himself yet again.
- The Chronicles of Thomas Covenant: Played with, the Ranyhyn are a herd of wild horses that possess phenomenal strength and endurance. The Lords who rule The Land regularly present themselves to the Ranyhyn, to see if the Ranyhyn deem them worthy. If a Ranyhyn horse deems a Lord worthy, it will rear to them and become that Lord's servant by staying close, coming when they whistle, and allowing Lord to ride him wherever he goes. If a Lord presents himself or herself to the Ranyhn and a Ranyhyn does not choose them, there is nothing preventing that Lord from continuing as a Lord, but there is still a question of why they were rejected. One Lord who was rejected and therefore has to ride an ordinary horse cannot keep up with other Lords who ride Ranyhyn with far greater speed and endurance. Even the Lords were confused as to why he was rejected, as he was a good and noble Lord. When Thomas Covenant came to the Land, over one hundred Ranyhyn reared to him, which astonished the Ramen whose work was to serve and care for the Ranyhyn, because on one had ever had more than one Ranyhyn accept them. However, it's made clear the Ranyhyn did so not out of respect, but because they were terrified of the power of the White Gold ring Covenant carried.
- The Histories: Exploited, in this story by Herodotus, he tells his account of the coronation of King Darius I of The Achaemenid Empire. It was declared that whoever could make their stallion whinny first before daybreak would be crowned king. Darius, being a Guile Hero, rubbed his hands over the genitals of a mare in heat, and then wafted them under his stallion's nose, arousing it into whinnying.
- Grandmaster of Demonic Cultivation: Mo Dao Zu Shi: Jin Guangyao compares his father disparagingly to a stallion for his philandering ways.
Jin Guangyao: An old stallion that gets in a rut wherever it goes really deserves such a death, doesnt it?
- A Song of Ice and Fire: The Dothraki are horse-worshipping nomads with a very macho culture and a prophecy about a "stallion who mounts the world". "Mounting" in this case meaning "have sex with".
- Last Week Tonight: Parodied in the episode about Gurbanguly Berdimuhamedov, the president of Turkmenistan associates himself with horses (specifically Akhal-Tekes) and John makes funs of this by implying that his love for horses borders on beastiality. Gurbanguly Berdimuhamedov has written books about horses, wrote poems about horses, enters horse competitions, made it illegal to rename horses, and calls himself the "People's horse breeder".
John Oliver: ""Witnesses never wearied of being astonished by the steed-and-human intercourse brought to full perfection..." Which I'm hoping is a mistranslation but probably isn't"
- Parks and Recreation: As the uber-celebrity of Pawnee Lil' Sebastian occupies this spot in a few of his memorial pictures since several people insist on using pictures of him fully erect.
- Game of Thrones: The Dothraki are associated with horses. The animals are an integral part of their culture. Khals are also known as horselords, they are renowned for their skill at mounted combat, they worship a deity known as the Great Stallion and there is a prophecy of a great "khal of khals" known as the 'Stallion who Mounts the World', who will unite all the people into one khalasar.
- The Boys: Invoked in Black Noir's animated flashback of Payback, where he sees the TNT Twins as a pair of horses. The TNT Twins were the hosts of Herogasm and were obsessed with hedonism and sexual pleasure.
- Classical Mythology:
- Centaurs were originally characterised as amorous warriors who were seen as wild, lawless, and inhospitable beings who were slaves to their "animal passions" (with wise Mentor Archetype Chiron being a rare exception).
- Satyrs were originally depicted by the Greeks as hairy men with the ears and tails of horses or donkeys and permanently-erect Gag Penises (which may or may not have been equine in appearance, Depending on the Writer) who spent all their time engaging in Black Comedy Rape against whatever crossed their paths. It wasn't until the rise of the Roman empire when they became associated with fauns that they gained their more well-known half-human/half-goat appearance.
- In some accounts, pagan Irish chieftains would have public sex with mares, symbolically taking the place of a stallion to demonstrate their virility. As these accounts come from later Christian monks eager to distance themselves from their heathen past, this may only have happened in their imaginations.
- The Elder Scrolls V: Skyrim: Invoked, the Stallion's Potion increases stamina by 20 points for 300 seconds and it's part of a Sidequest where it must be delivered to Raerek for his "special problem".
- God Of War 2: As the son of Poseidon, Theseus has a horse motif and this version of the character portrays Theseus as an old man whose glory days are far behind him. He proudly serves the Sisters of Fate for the glory of Zeus by looking after the steeds of time and he fights Kratos after deeming him weak for losing the fight against Zeus.
- Hotline Miami: Implied, the horse mask is called "Don Juan" and is in the reference to the Spanish nobleman who was famous for his high sex drive and seduction of women. The mask is also worn by The Girl in Jacket's meetings, who was a sex slave of The Director.
- Bojack Horseman: Deconstructed, Bojack is a washed-up Hollywood celebrity who has sex with a lot of women, but he does so to compensate for his loneliness and depression. It also bites him in the back, as he not only has a serious fallout with his ex-girlfriend Charlotte due to almost sleeping with her teenage daughter Penny, but also his relationship with his former co-star Sarah Lynn leads to her drug-induced death, which also ruins his entire career.
- Rick and Morty: Rickdependence Spray has a lot of sexual imagery and horses have a strong presence in the episode. Morty causes the invasion of giant mutant sperm by using a horse breeding mount to masturbate, the episode introduces the Chuds, a species of cannibalistic horses that have been at war with humans, and Rick drunkenly got one of their princesses pregnant and she orders a truce to save his life. The princess is called Poñeta, a Spanish term for masturbation, and one of the chuds proclaim that the pregnancy was all part of the prophecy that would unite the chuds and humans.
- In some European languages this association has led to call a sexually successful man "stallion" (e.g. Italian "stallone" and Russian "erebec"). In a twist of irony, the word "stud" itself is related to several Germanic cognates (e.g. German "die Stute", Swedish "sto") sharing the meaning "mare".
- Modern stallions, with notable exceptions, have been deprived of the natural act of reproduction, though not of their vaunted virility. As depicted in an older episode of the reality show Dirty Jobs, the stud deposits his seed into an artificial vagina, from which it is extracted into vials and frozen for later use. Both the stallion and mare are too valuable to allow them to actually touch each other. Thoroughbreds, however, must conceive naturally to be considered breed-conforming, which greatly increases their expense and risk of harm.
- Gurbanguly Berdimuhamedov, the president of Turkmenistan associates himself with horses as he has written books about horses, wrote a poem about one of his horses, enters horse competitions, made it illegal to rename horses, has horse-themed decorations in his office, and calls himself the "People's horse breeder".