• Four ethnic groups - the Hausa, Fulani, Yoruba and Ibos - make up 65% of the population.
• English is the official language but the ethnic languages are also widely spoken.
• The main religions are Islam and Christianity.

Oil and debt

Nigeria's economy is heavily dependent on oil, which provides the vast majority of the country's export earnings.

During the 1970s Nigeria experienced high levels of economic growth but its national debt also grew.

After repeatedly negotiating agreements with creditors Nigeria arranged a long-term structural programme with the International Monetary Fund in 1986.

Coups and politics

Nigeria gained independence from Britain on October 1, 1960. Since then its has had 27 years of military rule.

In 1964 the fledgling state's first elections were rife with malpractice and violence.

Major-General Johnson Aguiyi-Aronsi, an Ibo from the Eastern Region, staged a successful coup in 1966 and formed a Supreme Military Council.

Just six months later he was killed and Lieutenant-Colonel Yakubu Gowon, from the Christian North, seized power.

In 1967 relations between the Eastern Region and the federal government deteriorated.

The military Governor of the Eastern Region, Lt-Col Chukwuemeka Odumegwu-Ojukwu, announced their secession and proclaimed its independence as the Republic of Biafra.

Federal forces spent two years quelling the Biafra rebellion. Up to 1m people died mainly from starvation.

But Nigeria has also seen its influence grow with neighbouring countries, most recently in Sierra Leone, where Nigeria helped restore the democratically elected leader.