To colonize means to take control of a land and settle there, usually by force or without permission from the people already living there. When one country colonizes another place, it sends people to live there permanently and establishes its own government, laws, and customs over the original inhabitants.

Throughout history, powerful nations colonized distant lands they wanted to control. Spain colonized much of South and Central America starting in the 1500s. Britain colonized territories across the globe, including what became the United States, India, and Australia. France colonized parts of Africa and Southeast Asia. These colonizing powers often treated the native peoples terribly, taking their land, suppressing their cultures, and exploiting their resources.

Today, when we study history, understanding colonization helps explain why certain languages, religions, and customs spread around the world, and why some nations became wealthy while others struggled.

Scientists also use colonize differently: when bacteria colonize a surface, they establish themselves and multiply there. Similarly, when people talk about humans possibly colonizing Mars someday, they mean establishing permanent settlements, though unlike historical colonization, Mars has no existing population to displace.