Nigeria is a big country in west Africa, Nigeria became a formally independent federation in 1960. It experienced a civil war from 1967 to 1970. It thereafter alternated between democratically elected civilian governments and military dictatorships until it achieved a stable democracy in 1999, with the 2011 presidential election considered the first to be reasonably free and fair. Nigeria is often referred to as the "Giant of Africa", owing to its large population and economy. With 186 million inhabitants, Nigeria is the most populous country in Africa and the seventh most populous country in the world. Nigeria has the third-largest youth population in the world, after India and China , with more than 90 million of its population under age 18. The country is viewed as a multinational state as it is inhabited by 250 ethnic groups, of which the three largest are the Hausa, Igbo and Yoruba ; these ethnic groups speak over 250 different languages and are iden...