Biafara, anglicized as Biafra (/biːˈæfrə/ bee-AF-rə), officially the Republic of Biafra, was a partially recognised state in West Africa that declared independence from Nigeria and existed from 1967 to 1970. Its territory consisted of the former Eastern Region of Nigeria, predominantly inhabited by the Igbo ethnic group. Biafra was established on 30 May 1967 by Igbo military officer and Eastern Region governor Chukwuemeka Odumegwu Ojukwu under his presidency, following a series of ethnic tensions and military coups after Nigerian independence in 1960 that culminated in the 1966 anti-Igbo pogrom.

The Nigerian military attempted to reclaim the territory of Biafra, resulting in the beginning of the Nigerian Civil War. Biafra was officially recognized as a sovereign and independent country by Gabon, Haiti, Côte d'Ivoire, Tanzania, and Zambia while receiving de facto recognition and covert military support from France, Portugal, Israel, South Africa, and Rhodesia. After nearly three years of war, during which around two million Biafran civilians died, president Ojukwu fled into exile in the Ivory Coast as the Nigerian military approached the capital of Biafra. Philip Effiong became the second president of Biafra, overseeing the surrender of Biafran forces to Nigeria.

Igbo nationalism became a strong political and social force after the civil war. It has grown more militant since the 1990s, calling for the independence of the Biafran people and the establishment of their state. Various Biafran secessionist groups have emerged, such as the Indigenous People of Biafra, the Movement for the Actualization of the Sovereign State of Biafra, and the Biafra Zionist Front.

Early modern maps of Africa from the 15th to the 19th centuries, drawn from accounts written by explorers and travellers, show references to Biafar, Biafara, Biafra, and Biafares. According to the maps, the European travellers used the word Biafara to describe the region of today's West Cameroon, including an area around today's Equatorial Guinea. Between 1731 and 1754, German bookseller and publisher Johann Heinrich Zedler published his encyclopedia Grosses vollständiges Universal-Lexicon, in which he mentioned the exact geographical location of the capital of Biafara, namely alongside the river Rio dos Camaroes in today's Cameroon, at a latitude of 6 degrees 10 minutes. The words Biafara and Biafares also appear on maps from the 18th century in the area around Senegal and Gambia.

In his personal writings from his travels, the Rev. Charles W. Thomas defined the locations of islands in the Bight of Biafra as "between the parallels of longitude 5° and 9° East and latitude 4° North and 2° South."

In 1960, Nigeria became independent from the United Kingdom. As with many other new African states, the country's borders did not reflect earlier ethnic, cultural, religious, or political boundaries. Consequently, the northern region of the country has a Muslim majority, primarily encompassing the territory of the indigenous Sokoto Caliphate. The southern population is predominantly Christian, mainly encompassing the territory of the indigenous Yoruba and Igbo states in the west and east, respectively. Following independence, Nigeria was demarcated primarily along ethnic lines: a Hausa and Fulani majority in the north, a Yoruba majority in the West, and an Igbo majority in the East.

Ethnic tension had simmered in Nigeria during discussions of independence, but in the mid-twentieth century, ethnic and religious riots began to occur. In 1945, an ethnic riot flared up in Jos, in which Hausa-Fulani people targeted Igbo people and left many dead and wounded. Police and army units from Kaduna had to be brought in to restore order. A newspaper article describes the event:

At Jos in 1945, a sudden and savage attack by Northerners took the Easterners completely by surprise, and before the situation could be brought under control, the bodies of Eastern women, men, and children littered the streets and their property worth thousands of pounds reduced to shambles