Formed in 1975, the Tigray People's Liberation Front (TPLF) was dedicated to the overthrow of the Mengistu regime (see The Tigrayan Movement, ch. 4). It survived during its early years only because of the money and weapons it received from the EPLF. The EPLF supported the TPLF because the latter formed a buffer between the Ethiopian army and Eritrea. Despite subsequent political and ideological rifts between the groups, the EPLF always maintained this buffer strategy.

On February 18, 1976, the TPLF convened its first congress, at Dima. The group of about 170 people in attendance elected a seven-member Central Committee. During May and June 1976, the rebels gained international attention by kidnapping a British family and a British journalist. By the end of the year, the TPLF had about 1,000 full-time fighters. It confined its military activities to attacking traffic along the main road between Mekele, the Tigrayan capital, and Asmera. Within two years, however, the TPLF had increased its strength to the point where the group controlled large parts of the countryside and threatened the Ethiopian army's supply lines.

Throughout the late 1970s and the early 1980s, Tigray, like Eritrea, suffered from the Derg's annual military counteroffensives in north-central Ethiopia. During these operations, the TPLF and the EPLF coordinated many of their military actions against government forces. However, in 1983 a rift developed between the groups after the TPLF proposed a unification of all anti-Mengistu elements, including the EPLF. Relations further deteriorated when the EPLF failed to inform the TPLF that it had started secret peace talks with Addis Ababa. As a result, the TPLF refrained from supporting the EPLF during the government's 1985 counteroffensive in northern Ethiopia. Although there was a brief reconciliation after the EPLF's victory at Afabet, the TPLF-EPLF estrangement continued for the next several years. In March 1987, for example, the TPLF refused to be represented at the EPLF's Unity Congress.

In February 1989, the TPLF, which by then included at least 20,000 full-time fighters plus an unknown number of parttime fighters, abandoned hit-and-run guerrilla tactics. The TPLF, with support from the EPLF, which wanted to open a second front against Mengistu, launched a conventional attack against the town of Inda Silase in western Tigray. The TPLF destroyed a 20,000-member Ethiopian army force. Ethiopian military units then withdrew from Mekele and the rest of Tigray without a fight. This defeat undoubtedly helped trigger the unsuccessful May 1989 coup against Mengistu.

Although government troops subsequently returned to southern Tigray and reoccupied a few towns and villages, the political and military initiative remained with the TPLF. On March 10, 1989, the TPLF opened its third congress. Apart from passing numerous antigovernment resolutions, the delegates pledged to support the EPRDF, which had been formed earlier in the year by the TPLF and a group known as the Ethiopian People's Democratic Movement (EP 1000 PDM), whose members were primarily Amhara. In time, the EPRDF also included the Oromo People's Democratic Organization (OPDO) and the Ethiopian Democratic Officers' Revolutionary Movement, both of which had been created by the TPLF in May 1990. Tigrayan strategists hoped the unification of these groups eventually would enable the TPLF to widen its base of support beyond Tigray. Elements in support of the government, however, denounced the EPRDF as nothing more than a TPLF organization in Amhara clothing.

In August and September 1989, TPLF forces, operating within the framework of the EPRDF, moved south into Welo. They overran towns along the main road, routed numerous Ethiopian units, captured an array of Ethiopian army equipment, and forced the temporary evacuation of the regional capital of Dese. By the end of 1989, the EPRDF had succeeded in defeating an Ethiopian garrison at Debre Tabor. This victory enabled Tigrayan forces to cut the road between the cities of Gonder and Bahir Dar and to force their way into northern Shewa, less than 160 kilometers from Addis Ababa. Mengistu responded to these developments by persuading the National Shengo to order the mobilization of all former soldiers and police up to age seventy. Additionally, the National Shengo authorized increased military spending, assigned all transport to the war effort, and armed local populations in war zones. However, these actions failed to improve the government's battlefield performance against the EPRDF.

During 1990 the EPRDF, which controlled all of Tigray with the exception of one small government outpost, concentrated on consolidating the gains it had made the previous year, although in June the insurgents repulsed a major offensive by the Ethiopian army. The year 1991, however, saw the EPRDF launch three offensives in rapid succession that destroyed the Ethiopian army and the Mengistu regime. On February 23, the rebels began Operation Tewodros to drive the government out of Gonder and Gojam, and they succeeded after only two weeks of fighting. The inhabitants of both regions supported the operation largely because of their opposition to the heavy conscription campaign of the previous year and because of their hatred of the villagization program.

In March the EPRDF launched Operation Dula Billisuma Welkita into Welega, which resulted in the capture of the regional military headquarters in Nekemte. Insurgent units then advanced south and east and soon occupied Fincha, site of an electric power station that served Addis Ababa. In mid-May Operation Wallelign was begun along the Welo front. Within hours the rebels had overrun Dese and Kembolcha. By May 20, the EPRDF had captured all government positions in southern Welo and northern Shewa and were advancing on Addis Ababa from the west. The next morning, Mengistu fled the country.

In the aftermath of these three campaigns, the Ethiopian armed forces disintegrated. Tens of thousands of soldiers crowded into Addis Ababa and sold their weapons or used them to rob civilians. Countless other soldiers went home, while many senior army and air force officers fled to Djibouti, Kenya, or Sudan. Ethiopian naval personnel and vessels dispersed to Saudi Arabia, Yemen, and Djibouti.

During the final week of the war, the EPRDF slowly advanced toward Addis Ababa, capturing the air force base at Debre Zeyit along the way. The final battle for the capital occurred on the morning of May 28, when the EPRDF entered the city. Resistance to the takeover consisted largely of street fighting and a low-level clash at the Grand (Menelik's) Palace. About 600 to 800 people, both civilians and combatants, reportedly died during the operation. For the TPLF, the long road from the hills of Tigray had finally ended in victory.

Data as of 1991