Readers may have to wait a bit to find out what's up with the Starks and the Lannisters and whichever Baratheons are still kicking around. But if you're a fan of Westeros's favorite dragon-based family, then you're in luck: George R.R. Martin has graced readers with Fire and Blood, a new book dedicated to the reign of House Targaryen. Readers will almost certainly be treated some gory new details about Aegon's Conquest, the Dance of the Dragons, the Blackfyre Rebellions, and more fiery chapters from Westerosi history.
But... what about actual history?
It's no secret that GRRM has pulled heavily from real world history (plus dragons and ice zombies) for his plots—most of the "game of thrones" itself is borrowed from the English War of the Roses. The Starks and the Lannisters are patterned pretty closely after two of the major families that vied for power during that grim, multi-generation war... but there weren't exactly Lucius Malfoy-looking dragon-riders tearing up the skies over medieval England. So where did the Targaryens come from?
To begin with, Martin loves to mess with classic fantasy tropes, and the Targaryens are no exception: They fancy themselves ethereal and set apart from mere mortals, much like Tolkien's elves. They pride themselves on their rarefied connection to dragons, and they do seem to be mildly heat resistant. However, Martin proves over and over again that Targaryens are basically just normal people who use a lot of conditioner. Most of the family died in a fire years before the events of A Game of Thrones, so they're definitely not fire proof, and (in the books, at least) Dany seriously struggles to control her magical dragon babies.
So, in terms of literary history, the house of Fire and Blood is kind of like a bougie, mortal, less competent version of the hot, pale elves of Tolkienesque fantasy.
As far as real world connections go, however, the Targaryens seem to draw a heck of a lot of inspiration from three very different civilizations: the Romans, the Egyptians, and the Normans.
House Targaryen isn't native to Westeros, you see. They were once a noble family of Old Valyria. In Martin's world, Valyria was a civilization on a peninsula in a temperate sea, which grew into a vast empire. They conquered large swathes of the continent from dragon-back. They poured concrete and built roads, forged incredibly advanced weapons, and developed a system of government where a number of wealthy families would vote and rule together, rather than bowing to a single leader.
So... Rome. Valyria is basically the Roman Republic with dragons and blondes.
Much like Rome, the Valyrians shaped Europe/Essos in their image. In A Song of Ice and Fire, most people from Essos speak corrupted versions of Valyrian. In real life, many Europeans still speak "corrupted" versions of Latin, which split off into French, Spanish, Italian, and so forth over the centuries.
Also like Rome, Old Valyria eventually fell, although Martin's version is far more dramatic. His empire gets blown to smithereens in the Doom of Valyria, a cataclysm that utterly destroyed the entire peninsula. Think the destruction of Pompeii turned up to eleven.
The Targaryens were the only noble, dragon-holding family to escape the Doom, and they hung about for a while being sad before setting their sights on Westeros. The Roman Empire did conquer Britain as well — although Martin has flipped the timeline around a bit, since the Romans were in the British Isles long before the empire fell (they also did build a big wall up North to keep out the "wildlings," also known as the Scots).
So Martin definitely went for some Imperial Roman vibes with the Targaryens, but he borrowed from at least one other ancient super power as well: the Ptolemaic Dynasty of Egypt. They were also very into keeping their bloodlines "pure" — by any means necessary.
Yeah, the Ptolemaic Dynasty was way into incest. They frequently married brothers to sisters to try and maintain their royal "purity." And they named every freaking boy Ptolemy (girls were almost always Cleopatra, Berenice, or Arsinoe). They were also from Macedonia, but felt extremely justified in ruling Egypt anyway, a la the Targaryens waltzing into Westeros with their many, many Aegons.
All those "pure" generations of Ptolemies led to some not-so-stable rulers, although the Ptolemaic Dynasty was also known for some pretty powerful queens. The very last queen, Cleopatra VII (yes, that Cleopatra) was famous for her intelligence and leadership, and for being the first ruler in her family's 300-year reign to actually learn the Egyptian language and communicate with her subjects.
Honestly, the "benevolent ruler" bar is pretty low for Dany, too.
Last but not least, the Targaryens have a lot in common with the Normans, especially when it comes to conquering. Aegon's Conquest is basically a jazzed up version of the Norman Conquest, when William the Conqueror crossed the "narrow sea" from France and won control of the seven kingdoms of England. Of course, he did it all without flying lizard monsters, but the parallels are pretty clear.
The Normans themselves were descended from vikings who'd settled in France, intermarrying with the locals and adopting French culture. They made French the language of the English court, and set up the English monarchy to spend the next several hundred years whining about wanting to rule France, too. And then, after three centuries of ruling, the Norman dynasty ended with a usurper... much like Robert Baratheon busting in to take over from the Targaryens with his vague claim on the throne. Now, all of a sudden, just about any highborn family could stake their claim on the most powerful seat in the realm, opening up England/Westeros to the game of the war of the rose-thrones.
Given what happened to the Roman Empire, the final Cleopatra, and the unbroken line of Norman kings, things aren't looking too great for Dany's chances at that pointy chair. But then again... none of those fools had dragons. So, let's all just wait and see!