1000 years of European borders
Watching these colors (cultures) moving about competing for resources, power, etc., shines a light on one aspect of politics and society that we tend to forget.
Up until World War II the "right of conquest" was the rule of law. Then much of the world, still crippled from the war, agreed on the Nuremberg Principles. In 1974, on United Nations General Assembly Resolution 3314. Some of these principles can be traced back to Magna Carta. These modern goals are noble, but their nobility alone will not ensure their survival.
Just as tribes, herds, gaggles, brides, swarms and every other group of creatures that needs resources to survive have been in a constant battle and/or delicate balance of power since the dawn of time, so too is this the case for ideas, beliefs, or in general, memes.
Meme: an element of a culture or system of behavior that may be considered to be passed from one individual to another by nongenetic means, especially imitation.
Today it is clear to see we are in the middle of a global meme-war.
(Some bias is clear in these maps, and the music is comicly over-the-top)
It's easy to forget, or perhaps simply convenient, that Mongolian immigrants of 12,000 years ago successfully established themselves as the "Native Americans" by wiping out every trace of the aboriginal descendants who had been living unmolested in the Americas for 28,000 years.
Look at the ideological wars of today. We tend to reduce everything to black and white, left and right, but each of these supergroups is made up of many smaller, interdependent beliefs, desires, goals, etc., each one battling for control over their small patch of ideological turf. If we could map this out like these maps, we could see hundreds of these timelines for each shifting border between the battling "tribes" of beliefs, such as community and individual, morality and relativism, sanctity and impiety, responsibility, rule-of-law and rule-by-law, etc., etc.
In these battles is ideas there are no objective observers, for those without an idea in their head are the first to be conscripted, given all the available room in their empty head for ideas to be planted. This is also why the front-line leaders of these armies are often in the field of ideas, such as social sciences like sociology, psychology, and philosophy.
It's easy, even if not completely accurate, to see certain ideologies as viruses or parasites fighting for survival, some being the cultural equivalent of a flesh-eating disease, or smallpox, or maybe something parasitic, like toxoplasmosis, targeting the very foundation of human existence. The reality of history, as shown by these timelines, makes it clear that the battle for cultural survival is ever ongoing, and there are no Nuremberg Principles for ideological warfare, so the Rule of Conquest is still in play.
I have another oddly related post to this concept: Australian Cave paintings may be the oldest on the planet