Traditionally, the region around Lake Chad was a focal point for trans-Saharan trade routes. Arab traders penetrated the area in the 7th cent. A.D. Shortly thereafter, nomads from North Africa, probably related to the Toubou, entered the region; they eventually established the state of Kanem, which reached its zenith in the 13th cent. Its kings converted to Islam, the religion also practiced by the successor state of Bornu. The Wadai and Bagirmi empires arose in the 16th cent.; they warred with Bornu and in the 18th cent. surpassed it in power. By the early 1890s all of these states, weakened by internal dissension, fell under the control of the Sudanese conqueror Rabah el Zobaír (Rabih al-Zubayr).
French expeditions advanced into the region in 1890, and French sovereignty over Chad was recognized by agreements among the European powers. In 1900, French forces defeated Rabah's army, and by 1913 the conquest of Chad was completed; it was organized as a French colony in French Equatorial Africa and remained under military rule. Chad was later linked administratively with Ubangi-Shari (now the Central African Republic), but in 1920 it again became a separate colony. It was granted its own territorial legislature in 1946. In the French constitutional referendum of 1958, Chad chose autonomy within the French Community. Full independence was attained on Aug. 11, 1960, with Ngarta Tombalbaye as the first president.
Tombalbaye steadily strengthened his control over the country, and by 1965 it had become a one-party state. Chad suffered severely from the W African drought of the late 1960s and 1970s. Discontent among northern Muslim tribes with the increasing power of Tombalbaye's southern-dominated government evolved into a full-scale guerrilla war in 1966. French troops helped battle the revolt, which ended in 1973. However, the main Muslim guerrilla group, the Chad National Liberation Front (FROLINAT), figured prominently in fighting between Chad and Libya throughout the 1970s and 80s. During this period, Libya occupied various parts of Chad and supplied FROLINAT (which initially did not oppose Libyan expansionism) with arms.
Tombalbaye was killed in a coup in 1975. In 1979 a coalition government headed by Goukouni Oueddei, a former rebel from the north, assumed power, ending control of the government by southern Chadians, but he was overthrown in 1982 by the forces of former prime minister Hissène Habré. In 1987, the combined forces of FROLINAT and the Chadian government (with French and U.S. military aid) drove Libya from the entire northern region with the exception of the Aozou Strip and parts of Tibesti; in 1994 the International Court of Justice rejected Libya's claims and returned the area to Chad.
In 1990, Idriss Déby, leader of the Patriotic Salvation Movement (MPS), overthrew the Habré government and promised democratic reforms and a new constitution; Habré fled to Senegal. A national democracy conference in 1993 established a transitional government with Déby as interim president and called for free elections within a year. Armed rebel groups continued to challenge the government, which, for its part, repeatedly postponed the elections. Multiparty presidential elections were finally held in 1996; Déby was returned to office, and the MPS also triumphed in the 1997 legislative elections.
The late 1990s saw renewed fighting in the north and other parts of the country. The president was again returned to office in 2001 in a disputed election, and the following year the MPS again won the legislative elections. A peace accord was signed with rebels in the north in May, 2002, but fighting erupted there again in Jan., 2003. The same month the government signed a peace agreement with rebels in E Chad, and in the following December a new peace agreement was signed with the northern rebels.
Fighting between local rebels and government troops and militias in Darfur, Sudan, which began in early 2003, has driven tens of thousands of refugees into E Chad. There also have been clashes between Chad's army and the Sudanese militias, and Chad has accused Sudan of backing former Chadian rebels to fight against Sudanese rebels. Chad also has received refugees from the Central African Republic, 30,000 of whom fled a coup there in 2003 and smaller numbers that were displaced by banditry in 2005.
In May, 2004, Chad's national assembly approved a constitutional amendment that ended the two-term limit on the presidency, allowing Déby to run for a third term in 2006. The amendment was approved in a referendum in June, 2005. Desertions (Sept., 2005) from the Chadian army increased the number of rebels based in Darfur, and in December there was fighting between the rebels and the army in E Chad. Chad again accused Sudan of backing the rebels and called for international intervention in Darfur.
In Dec., 2005, the national assembly voted to allow the government to use oil revenues that were to be set aside, under an agreement with the World Bank, for poverty reduction projects and future uses. Chad said the change was necessary because of national financial difficulties, caused in part by the rebellion in the east. In response, the World Bank halted loans to Chad and froze a Chadian oil escrow account, but an interim agreement, reached (Apr., 2006) after Chad threatened to halt oil production, allowed Chad access to the escrow account. A new agreement on poverty reduction projects was signed with the World Bank in July, but two years later (Sept., 2008) the World Bank canceled an oil pipeline deal with Chad because the government had failed to live up to the agreement. Oil revenues also were a source of friction with foreign consortium producing the petroleum. In Aug., 2006, Chad threatened two foreign companies with expulsion until they agreed to pay a renegotiated tax bill, and the president called for Chad to be a partner in the consortium.
Meanwhile, the assembly voted in Jan., 2006, to postpone its elections for a year, until 2007, citing financial problems as the reason. Some observers, however, believed that the real reason for the postponement was to assure Déby of support in the national assembly. An agreement (Feb., 2006) between Chad and Sudan that was intended to end cross-border incursions had little immediate effect on the fighting in the region. In Mar., 2006, government forces foiled a coup plot against Déby, whose position seemed increasingly uncertain. The following month Chadian rebels mounted a drive that reached into the capital before it was defeated.
Déby was reelected in May, but the opposition boycotted the vote and denounced the election and the official turnout figure of 61% as frauds. The security situation remained unstable, with continuing militia incursions from Sudan into Chad and attacks by Chadian rebels in Chad, Sudan, and the Central African Republic. In November, in the southeast, Chad also endured attacks by Arabs on non-Arab Chadians. That same month the government agreed to the stationing of a proposed UN peacekeeping force on its side of the Sudan border, but three months later the government said it would not allow any military peacekeepers to be stationed in its territory.
The signing, in Dec., 2006, of a peace agreement with one group of rebels did not fundamentally alter Chad's deteriorated security situation. Fighting with the rebels continued sporadically into 2007. A clash with rebels in Apr., 2007, led to fighting between Chadian and Sudanese troops after Chadian forces crossed the border in pursuit of the rebels. The following month, however, both nations signed an agreement intended to bring peace to their border region. An accord between the government and opposition parties, signed in Aug., 2007, postponed the next round of national assembly elections until 2009 to create electoral lists and voter ID cards that would prevent fraud. Elections were not held, however, until 2011.
In September the UN Security Council authorized the sending of peacekeepers to Chad to protect refugees there, and the following month the government and the main rebel forces signed a peace accord. New fighting erupted in November, however, and in December Sudan accused Chad of mounting attacks in W Darfur in conjunction with rebels there. In Feb., 2008, the rebels advanced into the capital before being forced to retreat; government and rebel forces continued to battle in E Chad in subsequent months. Later in February the 3,700-member European peacekeeping force (EUFOR) began deploying in Chad to protect Sudanese and Chadian refugees. In Mar., 2008, the peacekeeping force came under UN command, and began the process of broadening its composition and increasing its size to more than 5,000.
Also in Mar., 2008, Sudan and Chad again signed another accord intended to pacify the area along their common border, but Sudan broke off relations for six months beginning in May, accusing Chad of supporting an assault by Darfurian rebels against Sudan's capital, and relations between the two nations remained tense. In May, 2009, Chad and Sudan signed a reconciliation agreement, but that same month Chad accused Sudan of supporting a rebel attack against the government, and then sent forces into Darfur in attacks on Chadian rebel camps. There were new talks between the presidents of Chad and Sudan in Feb., 2010. In the long-delayed national assembly elections, which were finally held in Feb., 2011, Déby's party and its allies won a majority of the seats. The main opposition parties accused the government of fraud, and refused to participate in the April presidential election, which Déby won by a landslide.