Conversation so far:
why was there a war between nigeria and biafra?
The conflict between Nigeria and Biafra resulted from political, economic, ethnic, cultural and religious tensions which preceded Britain's formal decolonization of Nigeria from 1960 to 1963.
how long did the war between Nigeria and Biafra last?
The war lasted 2 years, 6 months, 1 week and 2 days, from 6 July 1967 until 15 January 1970.

Question: who won?
Self-contained rewrite: who won the war between Nigeria and Biafra?