April 19 (Reuters) - Nigeria, Africa's most populous nation and biggest oil producer, goes to the polls to elect a new president on Saturday.
Following is a chronology of Nigeria's struggle towards democracy.
Oct. 1960 - Britain grants independence with Abubakar Tafawa Balewa as prime minister.
1963 - Nigeria becomes a republic. Nnamdi Azikiwe becomes non-executive president and ceremonial head of state.
1966 - Nigeria's first coup ends civilian rule. Major-General Johnson Aguiyi-Ironsi becomes head of state but dies in July in a counter-coup bringing Lieutenant-Colonel Yakubu Gowon to power.
May 1967 - After a series of massacres of ethnic Ibos from the east of Nigeria, the eastern region tries to secede under the name of Biafra, under Lieutenant-Colonel Chukwuemeka Odumegwu Ojukwu. Civil war starts as federal forces attack.
Jan. 1970 - Civil war ends with defeat of secessionist Biafra. Gowon announces plans to restore civilian rule in 1976.
July 1975 - Gowon is toppled in coup which brings Brigadier Murtala Mohammed to power.
Feb. 1976 - Mohammed is assassinated in an abortive coup. His deputy, General Olusegun Obasanjo, takes over.
Oct. 1979 - Obasanjo steers country to elections and Shehu Shagari becomes civilian president.
1983 - Elections marred by widespread fraud. Months later General Muhammadu Buhari takes over from Shagari in an almost bloodless coup. He cracks down on crime and corruption but sets out no clear schedule for a return to civilian rule.
Aug. 1985 - Bloodless coup brings General Ibrahim Babangida to power.
June 1993 - Babangida annuls presidential election as businessman Moshood Abiola is poised to win. Babangida steps down and names an interim government which is overthrown in November by its defence minister, General Sani Abacha.
June 1998 - Abacha dies suddenly while preparing to stand as sole candidate in presidential elections. General Abdulsalami Abubakar takes power and promises to restore civilian rule by May 1999.
Feb. 1999 - Obasanjo, now a civilian, wins presidential election with 63 percent of the vote.
2000 - Thousands of people are killed throughout northern Nigeria as non-Muslims opposed to the reinforcement of Islamic Sharia law fight Muslims who demand its implementation.
May 2003 - Obasanjo is sworn in for a second and final four-year term after elections which international and local observers say were marred by widespread rigging. May 2006 - Senate rejects a proposal to amend constitutional term limits, preventing Obasanjo from seeking a third term.
April 14, 2007 - Elections for state governors and state assemblies take place, marred by widespread abuses and violence that kills about 50. The ruling People's Democratic Party wins 27 of 34 states declared, with two states to be re-run.
April 21 - Nigerians elect a successor to Obasanjo.
