colonization

Concise Oxford English Dictionary © 2008 Oxford University Press:
colonize /ˈkɒlənʌɪz/ (or colonise)

▶verb

• 1 establish a colony in (a place).

  ■ establish control over (the indigenous people of a colony).

• 2 appropriate (a place or domain) for one's own use.

• 3 Ecology (of a plant or animal) establish itself in (an area).

– derivatives
colonization noun,
colonizer noun.