Quartz has an excellent dynamic graph that shows where people are currently migrating—Africans to Europe, South Asians to the United Arab Emirates, Mexicans to the United States, and so on.
We are the animal that gets around. 250,000 years ago, a group of Africans left the motherland and in no time settled in Europe, Asia, North/South America, Australia. Humans try not to get stuck in a bad place; when a place becomes too dangerous, we know it's time to go elsewhere.
Indeed, people are in the habit of saying that the African ancestors of black Americans were forced to come to the US, whereas those of white Americans had the freedom/luxury to chose to stay in or leave Europe, but fleeing persecution, war, or a famine is anything but an act of freewill.