The Second Nigerian Republic was a brief formation of the Nigerian state which succeeded the military governments formed after the overthrow of the first republic. Background Contested elections and political turbulence in the Western region ended Nigeria's First republic in 1966 with the overthrow of the government by majors of the Nigerian army. A unitary style of government was subsequently decreed into law. After a counter-coup six months later, the country was drawn into a civil war between federal forces and Biafran forces (Eastern region). Just before the war, 12 new states were created from the four regions. After the victory of federal forces in 1970, the country began a period of economic boom fueled by increasing oil production and rising oil prices. The Nigerian governing structure was further broken up with the creation of smaller states in 1976, bringing the total number of states to 19. Founded (1979) Following the assassination of Nigerian military Head of State, General Murtala Mohammed in 1976, his successor General Olusegun Obasanjo initiated the transition process to terminate military rule in 1979. A new constitution was drafted, which saw the Westminster system of government (previously used in the First Republic) jettisoned for an American-style Presidential system. The 1979 constitution mandated that political parties and cabinet positions reflect the "federal character" of the nation — Political parties were required to be registered in at least two-thirds of the states, and each state was required to produce at least one cabinet member. A constituent assembly was elected in 1977 to draft a new constitution, which was published on September 21, 1978, when the ban on political activity was lifted. In 1979, five political parties competed in a series of elections in which Alhaji Shehu Shagari of the National Party of Nigeria (NPN) was elected president. Obasanjo peacefully transferred power to Shagari, becoming the first head of state in Nigerian history to willingly step down. All five parties won representation in the National Assembly. In August 1983 Shagari and the NPN were returned to power in a landslide victory, with a majority of seats in the National Assembly and control of 12 state governments. But the elections were marred by violence and allegations of widespread vote rigging and electoral malfeasance led to legal battles over the results. In the widely monitored 1979 election, Alhaji Shehu Shagari was elected on the NPN platform. On October 1, 1979, Shehu