It is true that the West went through the turbulent "Migration Period" from the roughly the late 4th to early 9th centuries AD, which brought in a significant population of new Germanic tribes of various Goths as well as people who weren't even Indo-European, like the Magyars (modern-day Hungarians). However, you are completely wrong in assuming that these newcomers supplanted entire populations via forced resettlement or genocide (the only two possible options there if they were supplanted). Usually the influx of new people and conquerors were relatively smaller than the people already settled in fixed locations, so even if their culture came to dominate, their genes didn't necessarily do so (instead melding in with the local population over time). Take for instance the Norman invaders of England who conquered the Anglo-Saxons, introducing into the British Isles a far smaller number of Normans compared to the overall existing native population. Obviously the Normans (who themselves were "Romanized" and "Gallicized" descendants of Vikings and Salian Franks) didn't kill every Anglo-Saxon to a man; they ruled over the Anglo-Saxons and their cultures eventually blended to form Anglo-Norman and finally English proper by the 14th century. Fun fact: a lot of those "Anglo-Saxons" themselves weren't even descended from the original Anglo-Saxons, but native Celtic Britons who appropriated their culture after the Anglo-Saxons conquered sub-Roman Britain. In either case, Europe's DNA on the whole isn't that different from ancient Europe,
according to this study.
As for Mediterranean people being olive-skinned compared to people descended from Celtic and Germanic people (enormous numbers of whom became Roman citizens), I think you're playing up the differences here a bit too much. Are modern-day Swedes different genetically from the population groups of northern Italians? Sure; even their facial phenotypes, hair, and eyes are sometimes easy to tell apart. That doesn't negate the fact that all European peoples share some level of genetic affinity, or the fact that there are plenty of blonde-haired, blue-eyed Italians. Take for instance one of my favorite Italians, Chiara Ferragni:
Even in Roman times this genetic diversity more or less matched modern-day European territories that were once ruled by Rome. An ancient mural from Herculaneum:
The blonde dude on the right is a Roman, not a Swede.
What?
Now you've absolutely lost me, bro. Jesus, I think my IQ just dropped a notch after reading this. When was Europe ever "largely dominated" by "Black" cultures aside from present-day African-American hip hop culture? Dear God, I hope you're not one of those people who think that the medieval Moors who invaded Sicily and Iberia were Sub-Saharan "blacks" instead of brown North African Berbers. I think you've been watching Dennis Hopper in the movie
True Romance a few too many times.
Genetic studies show that roughly 7% of modern-day Portuguese, Spaniards, and Sicilians share genetic affinity (via male-inherited Y-Chromosomal DNA) with North African Berbers, not sub-Saharan blacks. The Ghana and Mali Empires existed in West Africa at the time (true black civilization there), but they had little to no bearing on what was happening in Iberia before the Spanish Reconquista, and certainly were not the same people as the Berber-speaking Moors. Your argument is also strange for assuming that Middle Eastern culture dominated all of Europe in the early Middle Ages, when the Muslims didn't even manage to conquer all of Visigothic Iberia (the Christian Kingdom of Asturias still existed in the north, which gradually morphed into the Kingdom of Leon and Castile). Moorish rule over Sicily was even more ephemeral and short-lived, with the Normans booting them out in the 11th-century (two centuries before Islamic Cordoba fell to Christian Castile, meaning only the small territory in and around Granada was held by the Muslims in Spain from the 13th to 15th centuries). By "Middle Eastern" I hope you're not honestly suggesting or lumping them in with the Byzantines in Greece and the Balkans.
And the Celts and Germanic peoples like the Franks weren't "respectable" peoples? WTF are you talking about? WTF does this even mean? The Franks established their own kingdom in Gaul with Clovis I (r. 509-511), long before the late medieval decline of the Arab world and Islamic Golden Age. The Franks were eventually responsible for the establishment of the Carolingian Empire under Charlemagne and the Holy Roman Empire in the 9th century AD. Meanwhile, Celts in early medieval Ireland (before the Norman invasion) produced some of the most influential monasteries in the region that sent missions into the British Isles and theologian scholars like John Scottus Eriugena (815-877 AD) to the court of the Carolingian kings in France. Honestly, where the hell are you getting these bizarre ideas about history? From a modern-day Saudi elementary school textbook?
Seriously? That's what you think? It's okay if you don't know much about East Asian history, but being a fan of it myself, I can't let this slide.
For starters, the Ottoman Turks continued enslaving Europeans (and making Christians convert to Islam via the Janissary corps) well into the Early Modern Era, long after they conquered the last vestiges of Byzantium at Constantinople. So there you go, that's one example after the Arabs you ignored (or were fantastically ignorant about).
Now for East Asia: there's not a huge laundry list of historical episodes of "white oppression" in East Asia, because "whites" were in limited supply there throughout the centuries, naturally. That doesn't mean we can't point to some known examples. Let's start with the Tarim Basin, modern-day Xinjiang, that was conquered by the Chinese Han Dynasty in the 1st century BC at the conclusion of their long struggle with the rival nomadic Xiongnu (originally of Mongolia, perhaps related to the Huns). The oasis city states like Kucha and Kashgar, which originally bowed to the Xiongnu, now paid tribute to the Han emperors of China that imposed the Protectorate of the Western Regions over these Indo-European peoples descended from Tocharians. Although the Han Dynasty fell in 220 AD, the region was also brought into the Chinese sphere of influence and control in later dynasties like the Tang, while the Mongol-led Yuan Dynasty and Manchu-led Qing Dynasty also controlled the Tarim Basin. During the Tang Dynasty, although the Turkic tribes like the Gokturks had previously moved in and taken over, there were still plenty of Tocharian peoples living in the region. The Tang Empire imposed lots of strict marriage laws on these foreign peoples and others when it came to marrying native Han Chinese women. Just for fun, here's a 9th-century mural from Bezeklik, Xinjiang showing a red-haired, blue-eyed Caucasian Buddhist monk praying with a Chinese one:
And LOL at the idea that East Asians have always been isolationists. That might have been the case in certain periods, like when the Ming Dynasty stopped all foreign trade and tributary missions except for maintaining a handful of seaports along the South and East China Seas. However, this was the same Ming Dynasty that invaded Sri Lanka in the Indian Ocean in the year 1411 with Zheng He's Treasure Fleet and replaced the Sinhalese ruling house with a ruler friendly to Ming China. How about Imperial China's various attempts to conquer Mongolia, Vietnam, Korea, even Japan? How about the Eastern Han's brief war with the Kushan Empire of Afghanistan and northern India in 90 AD (the Chinese commanded by protector general Ban Chao)? Jesus Christ, man, how about the 13th-14th century MONGOL EMPIRE: do those two words even need more explanation? How about the Mongols conquering most of Ukraine and Russia and subjugating whites there from the 13th to 15th centuries? Let alone the Mongol invasions of Georgia, Armenia, and the rest of the Caucuses.
You want other examples, outside of China? Okay. How about medieval Japan, where the Ainu people (a Caucasian people) native to Hokkaido and formerly northern Honshu were eventually conquered and subjected by the "Wajin" (i.e. the Japanese) from the 14th to 16th centuries, including the suppressing of revolts to Japanese rule? The Japanese imposed exclusionary laws on the Ainu to make sure their communities operated separately from the Japanese. Punishment of Ainu for revolting was often very brutal.
Should we consider the Arab conquest and occupation of Sassanid Persia an instance of "whites" being oppressed? The Persians have historically been considered "Aryan" after all. Iran's current supreme leader Khamenei certainly looks white to me.
Just remove the turban and give him a John Deere hat, and he'll be as Murican as they come.