On January 25, 1971, Idi Amin Dada took advantage of the turmoil in the military, the weakened popular support for the government, and Obote's absence while attending the meeting of Commonwealth Conference of Heads of Government at Singapore to seize control of the government. Claiming himself to be a professional soldier, not a politician, Amin promoted many of his staunchest supporters, both enlisted personnel and officers, to command positions. Nepotism received widespread publicity, as a number of laborers, drivers, and bodyguards became high-ranking officers, although they had little or no military training. Army recruiters suspended educational requirements for military service, sometimes forcing groups of urban unemployed to volunteer. After the army had established control over the civilian population, Amin unleashed a reign of terror against Uganda that lasted almost until the end of the decade.

The army changed composition under Amin's rule. By 1977 it had grown to 21,000 personnel, almost twice the 1971 level. Amin killed many of its more experienced officers and imprisoned others for plotting to weaken or overthrow his regime. A few fled the country rather than face the mounting danger. Amin also increased the number of military recruits from other countries, especially Sudan, Zaire, and Rwanda. By 1979 foreigners accounted for nearly 75 percent of the army, exacerbating problems of communication, training, and discipline. The government barely controlled some army units. A few became quasi-independent occupation garrisons, headed by violence-prone warlords who lived off the land by brutalizing the local population.

Amin established several powerful internal security forces, including the State Research Bureau (SRB) and Public Safety Unit (PSU). Both terrorized local populations. By 1979 they had expanded to include about 15,000 people, many of whom acted as informers on fellow citizens. The SRB and PSU were responsible for as many as 250,000 deaths. Their victims included people from all segments of society and were accused of speaking or acting against the regime. One official observer estimated that twothirds of Uganda's technocrats died or fled into exile during the 1970s. Amin also ordered the expulsion of the country's Asian community, which numbered approximately 70,000. These and other excesses drained the nation's human and financial resources cash crop cultivation dwindled, most manufacturing ceased, and the economy collapsed. Social services, local government, and public works activities were almost non-existent.

By late 1978, Amin had laid the groundwork for his downfall by eliminating many moderate political and military leaders. His actions intensified rivalries within the army, which destroyed the alliance among factions from the northwest who had remained loyal to Amin. Sudanese and Kakwa soldiers then sought to weaken each other's influence, leading to violent disputes and mutinies within commands. To defuse these tensions, Amin deployed the rebellious Suicide Battalion from Masaka and the Simba Battalion from Mbarara to annex an 1,800-s95f -square kilometer strip of Tanzanian territory north of the Kagera River, known as the Kagera Salient (see fig. 1). Tanzania's president, Julius Nyerere, responded with force, and within two months the Tanzanian People's Defence Force (TPDF) had expelled the Ugandans from the salient.

On November 14, 1978, Nyerere ordered the TPDF to invade Uganda and oust Amin. About 1,000 Ugandans who had been in exile in Tanzania and had organized themselves into the Uganda National Liberation Army (UNLA) accompanied the TPDF invasion force. The TPDF-UNLA force numbered about 45,000. They launched a twopronged attack supported by long-range artillery. One group captured the southern town of Masaka near Lake Victoria the other advanced to the west of Masaka, moving northward through Mbarara and then east to Kampala.

By mid-March 1979, about 2,000 Libyan troops and several hundred Palestine Liberation Organization (PLO) fighters had joined in the fight to save Amin's regime however, this intervention failed to stop the TPDF-UNLA force. Entire garrisons of government troops mutinied or deserted when they realized that Amin would lose his hold on the government. Finally, on April 10, 1979, Kampala fell. Amin went into exile in Tripoli, Libya, and approximately 8,000 of his soldiers retreated into Sudan and Zaire. The TPDF eventually withdrew from Uganda, and the victorious UNLA established an unstable government to restore peace and stability.

Data as of December 1990