Why is English spoken in other countries?

English is spoken as the native language in countries such as English. It's spoken as the language of colonization and settlement in other countries such as Nigeria. It also is spoken as the second language of choice in required language learning in schools in such countries as the Netherlands and Portugal. And it's spoken as the official language in countries such as India where the linguistic situation is so explosive as to preclude one native language achieving such dominance over others. And it also is spoken as the language of diplomacy, international business and politics, science, and technology in many countries of the world.