Answer
The war was fought in Nigeria between the government of Nigeria and the secessionist state of Biafra. Biafra represented nationalist aspirations to the Igbo people whose leadership at the time felt like they could no longer coexist with the northern dominated federal government. The conflict resulted from political, ethnic, cultural, economic and religious tensions, which later preceded Britains formal decolonization of Nigeria.
Explanation:
Dude it's the Declaration of Independence <span />
Unity was brought mainly by the decades-long process of setting up and expanding the European Union in the aftermath of WW 2; also the disappearance of the Iron Curtain in 1989 was a major factor in uniting Europe.
Major disruptive factors were of course the two World Wars, and before 1989, the existence of a Communist-dominated Eastern Europe versus Western Europe.
