Short answers, pulled from the story.
Colonialism began in 1518 with a disease that killed half the native population of Hispaniola. This biological catastrophe served as the opening act of a global project that eventually spanned 84% of Earth's land by the beginning of World War I.
The Spanish Crown and Portuguese Empire divided the world between them in the Treaty of Tordesillas in 1494. This agreement was driven by the discovery of sea routes by Prince Henry the Navigator and established trading posts and conquered land without the consent of the people living on it.
The European colonial system took approximately 11 million Africans to the Caribbean and to North and South America as slaves between 1450 and 1870. The Portuguese Empire brought 3,646,800 slaves to Brazil, while the British Empire transported 1,665,000 to the British Caribbean.
By 1880, Africa was largely uncolonized, but by 1913, almost the entire continent was under European control. The territorial boundaries imposed by European colonisers defied existing boundaries of native populations that had previously interacted little with one another.
The United Nations issued the Declaration on the Granting of Independence to Colonial Countries and Peoples in 1960. This document affirmed the stance on independence, though colonial empires such as France, Spain, the United Kingdom, and the United States abstained.
900,000 French colonists, known as the Pied-Noirs, resettled in France following Algeria's independence in 1962. A significant number of these migrants were also of Algerian descent.