On its third anniversary as an independent nation, Nigeria became a republic.

Nigeria, officially the Federal Republic of Nigeria, is a country in West Africa. It is situated between the Sahel to the north and the Gulf of Guinea in the Atlantic Ocean to the south. It covers an area of 923,769 square kilometres (356,669 sq mi). With a population of more than 230 million, it is the most populous country in Africa, and the world's sixth-most populous country. Nigeria borders Niger in the north, Chad in the northeast, Cameroon in the east, and Benin in the west. Nigeria is a federal republic comprising 36 states and the Federal Capital Territory, where its capital, Abuja, is located. The largest city in Nigeria by population is Lagos, one of the largest metropolitan areas in the world and the largest in Africa.

The First Republic was the republican government of Nigeria between 1963 and 1966 governed by the first republican constitution. The country's government was based on a federal form of the Westminster system. The period between 1 October 1960, when the country gained its independence and 15 January 1966, when the first military coup d’état took place, is also generally referred to as the First Republic. The first Republic of Nigeria was ruled by different leaders representing their regions as premiers in a federation during this period.

October 1 is the 274th day of the year in the Gregorian calendar; 91 days remain until the end of the year.