2002: Jan1, Feb 23*, March 29-April 1, May 24*, Oct 1, Dec 6*, 25, 26.

*These holidays are dependent on the Islamic lunar calendar.

Nigeria's political and economic development has been hampered by ethnic rivalry and a volatile religious mix. Its international reputation has been tarnished by corruption, drug smuggling and fraud.

In 1966, after six turbulent years of civilian rule, army officers of the Igbo ethnic group -- the largest after the Hausa/Fulani in the north and Yoruba in the southwest -- staged a coup. Northerners staged a counter-coup in July 1966, and installed General Yakubu Gowon as head of state. The Igbos then declared the independent state of Biafra, triggering a civil war that ended in 1970 after up to one million people had died, many from starvation. After defeating the Igbos, a campaign of reconciliation started under Gowon, his successor General Murtala Muhammed and, later, General Olusengun Obasanjo, a southerner.

In 1979, Shehu Shagari, a northerner, became the first civilian president in 13 years. The military ousted him on New Year's Eve 1983, accusing his administration of corruption. Shagari was succeeded by General Muhammadu Buhari, a stern northerner who jailed around 500 politicians, officials and businessmen, and embarked on an austerity campaign. Buhari fell in a coup led by General Ibrahim Babangida, another northerner widely acclaimed after Buhari's toughness.

In 1986, Babangida introduced market reforms, freeing exchange and interest rates, leading to a sharp drop in the value of the naira currency, while lending rates rose to more than 40 percent.

Economic tension exploded in riots in 1992 in Lagos, Nigeria's commercial centre after Abuja became the capital. Persistent Christian-Moslem frictions led to major clashes in the northern Kano State, where 3,000 people were killed.

In June 1993, Babangida annulled presidential elections dubbed free and fair and widely believed to have been won by millionaire businessman Moshood Abiola, precipitating the worst political crisis in the country since the civil war.

Babangida was forced to surrender power to an unelected industrialist, Ernest Shonekan, to complete the transition. But Shonekan was ousted by his defence minister, General Sani Abacha, who became head of state and set up a constitutional conference to draw up a new system of government. Abiola, backed by a coalition of politicians, retired army brass and pro-democracy activists, proclaimed himself president in 1994 at a secret gathering in Lagos.

Abiola was arrested and charged with treason. The clamour for his release led to strikes set off by workers in the vital oil sector which dislocated fuel supplies with devastating consequences on transport, power, water and brought Nigeria to a standstill.

In October 1996, Abacha announced a programme to hand over power to civilians in three year's time. Nigerian pro-democracy activists feared the transition from military rule could be jeopardised by politicians' attempts to postpone key elections until 1998. The country's five political parties asked the electoral commission and other agencies supervising the transition programme to consider delaying state assembly and governorships polls set for later this year and holding them along with federal polls in late 1998.

The 1995 hangings of writer Ken Saro-Wiwa and eight other members of the Movement for the Survival of Ogoni Peoples for the murder of four pro-government Ogoni chiefs caused international isolation of Nigeria but not an embargo of its oil exports.

Abacha died suddenly in June 1998, and General Abdulsalam Abubakar became

Chief M. Abiola

the new head of state. Abubakar released some prominent political prisoners but within a month of his elevation,

Abiola died while still in detention, plunging the country into yet another crisis.

Abubakar abandoned Abacha's discredited democracy programme; scrapped five political parties and the National Electoral Commission and announced new plans to restore civilian rule and hand power to a democratically elected government in May 1999. A 14-member electoral commission was appointed by Nigeria's military Provisional Ruling Council to oversee a plan to restore democracy by preparing guidelines and a timetable for elections to restore civilian rule.

Polling for the country's 774 local councils was held in December 1998. The contest, the first free elections to be held since the annulled presidential elections in June 1993, resulted in a landslide victory for the centrist People's Democratic Party (PDP) formed in August.

The PDP won a majority in elections for Nigeria's legislature in February 1999 and its candidate, former military ruler General Olusegun Obasanjo, won nearly two-thirds of the votes in the presidential elections. He was sworn in on May 29.

The civilian government's introduction of sharia -- Islamic law -- in some northern states has divided Nigeria along religious lines. More than a thousand people died in sectarian bloodshed in the northern city Kaduna during 2000 as Christians and Moslems clashed over plans to proclaim sharia in Kaduna state.

The Kaduna riots triggered revenge killings of Muslims in southeastern Nigeria. About half a dozen of the 19 states of the predominantly Muslim north have either adopted sharia law or are in the process of doing so.

Youths in Kaduna petrol-bombed churches and Christian-owned shops in October 2001 in an area adorned with pictures of Saudi-born dissident Osama bin Laden, suspected by the United States of masterminding September 11 attacks in New York and Washington.

Local community leaders in the northern city of Kano said that as many as 200 people were killed after anti-American protests in mid-October sparked violent riots.

Tensions were high in Benue state in Nigeria’s main farming region in the centre of the country in late October 2001 after ethnic Tiv militia killed 19 soldiers who said they were on a mission to stop fighting between the Tiv and other groups such as the Jukun. Survivors and regional officials said more than 200 villagers were killed by soldiers who launched a crackdown after their colleagues were buried. Tens of thousands fled the region.

Oil companies are moving activities offshore to avoid the unrest, and leaders worry it will scare away foreign investment. Nigerians fear the violence will escalate still further before elections in 2003.