The answer is, surprisingly, not so long ago. Civilization was invented by the Chinese, the Egyptians, the Sumerians, etc., none of whom were white. All of these early civilizations probably thought they were cooler and more badass than anybody else, like all arbitrary collections of humans usually do, from tribes to neighborhoods to military units to Philadelphia Eagles fans, and they would have laughed at the idea that they were inferior to whites, who at the time were living in smelly lean-tos in Europe, having spear fights with each other and occasionally providing nourishment for wolves and bears.
The Greeks became the first white people to take a stab at civilization. They invented science, drama, philosophy and long, boring epic poems. They took sculpture to new heights, although they apparently thought only men with small penises were worthy models for their statues, or else those guys were forced to model only on really cold days. Finally, they picked up a rookie warrior from the minor leagues of Macedonia to spread their civilization all over the world. There is no evidence that Alexander the Great thought much about white supremacy, though. Anyone with a yearning for a career in the rape-and-plunder field was welcome to join his forces.
It fell to the Romans to be the next hot white thing, and they did the job proud, ruling their patch of the world for 800 years by wearing skirts, helmets with toilet brushes on top and using their short swords to chop up anybody who laughed at their wardrobes. They chopped up the white people of Gaul and the swarthy folks of Carthage equally, however, so playing the race card to a Roman legion did not result in you not getting slaughtered, or even being left in more generous bits.
The Roman Empire finally fell, and the ancestors of today’s white supremacists celebrated by becoming peasants under the yoke of the Catholic Church, and got their fun from burning heretics and having plagues. They eventually got into religious warfare, which had been invented by the Jews and perfected by the Muslims, but which white people went at with great enthusiasm. This caused them to develop better weapons than anybody else. When they got tired of fighting people equally well-armed, they said to themselves, “Hey—let’s try out some of these muskets and galleons on those people that Chris Columbus just discovered.” They went to the Americas and found that cannons and steel swords worked great against spears and stone axes. Then they discovered that you could easily convert the locals to Christianity at gunpoint and then they would build cathedrals for you. The first inklings of white supremacy were stirred.
In no country was the concept of white supremacy received more enthusiastically than in a boggy island in the North Atlantic called Britain. This nation of pale alcoholics went off to conquer the world and, between gin breaks, succeeded at most of it, including many parts of it that had been pre-conquered by other white people. They only had trouble with a breakaway bit in North America that eventually turned itself from a hodgepodge of querulous states to the greatest nation on Earth. White supremacists were happy to go along for the ride.
One of their major achievements was to raise the bar for whitehood extremely high—at one point in the US, such obviously melanin-deprived people as the Irish and the Poles were written off as non-white. Likewise, those Greeks and the descendants of the Romans were derided as dark and inferior. Popular feelings ran high against non-Anglos, and campaigns were organized to keep them out of the country. These didn’t succeed, as the growing nation needed these people to do its manual labor and later on, fight in World Wars.
Today, white supremacy is far more sophisticated and thoughtful in the US. Far from being looked-down upon, Irish-Americans and Polish-Americans are now freely afforded the opportunity to become white supremacists themselves. In this ongoing spirit of tolerance, the Greeks and the Italians have been let back into the white club, too, especially when Steve King speaks fondly about western civilization, which they started and which King regularly claims is endangered by Mexicans.
Funny thing is, though, without western civilization, we wouldn’t have Mexicans at all.