Colonization is a trilogy of books written by Harry Turtledove. It is a continuation of the situation set up in the Worldwar four-book series, projecting the situation between humanity and the Race (the bipedal lizardlike invaders and settlers from Worldwar) nearly twenty years forward into the first half of the 1960s.

The Race has settled and plans to colonize nearly half the surface of the Earth. This half includes Africa, Australia, China, southern Asia, Central America, and South America. The United States, the Soviet Union, the Greater German Reich (Germany and the territories it occupied during World War II), Great Britain, and Japan are the other major powers when the Race's colonization fleet of 80,000,000 to 100,000,000 settlers arrives. Humanity and the Race are still jockeying for advantages over each other.

Books of the Colonization trilogy are:

  • Colonization: Second Contact (1999)
  • Colonization: Down to Earth (2000)
  • Colonization: Aftershocks (2001)