The War in Abkhazia was fought between Georgian government and paramilitary forces, and a coalition of Abkhaz separatist forces and North Caucasian militants between 1992 and 1993. Ethnic Georgians who lived in Abkhazia fought largely on the side of Georgian government forces. Ethnic Armenians, who formed the Bagramyan Battalion and Russians within Abkhazia's population largely supported the Abkhazians and many fought on their side. The separatists received support from thousands of North Caucasian and Cossack militants and from the Russian military forces stationed in and near Abkhazia. Ukrainian volunteers fought on the Georgian side. The conflict coincided with the civil war within Georgia proper, where supporters of the ousted president Zviad Gamsakhurdia clashed with the post-coup government led by Eduard Shevardnadze.
Significant human rights violations and atrocities were reported on all sides, peaking in the aftermath of the Abkhaz capture of Sukhumi on 27 September 1993, which was followed by a large-scale campaign of ethnic cleansing against the ethnic Georgian population. A fact-finding mission dispatched by the UN Secretary General in October 1993 reported numerous and serious human rights violations committed both by Abkhazians and by Georgians. Approximately 5,000 ethnic Georgians and 4,000 Abkhaz were reported killed or missing, and 250,000 Georgians became internally displaced or refugees.
The war heavily affected post-Soviet Georgia, which suffered considerable financial, human and psychological damage. The fighting and subsequent continued sporadic conflict have devastated Abkhazia.
The situation in the Autonomous Soviet Socialist Republic of Abkhazia was tense in the late 1980s amid the collapse of the Soviet Union. Abkhazia, a multiethnic autonomous republic within the Georgian Soviet Socialist Republic, had a population of which 45.7% were Georgians and 17.8% were Abkhazians, while the remainder were other ethnic groups, including Armenians and Russians, according to the 1989 Soviet census. On 18 March 1989, the Lykhny Appeal was issued at a meeting in the eponymous village, signed by the first secretary of the Abkhaz Regional Committee of the Communist Party of the Soviet Union, Boris Adleyba, and the chairman of the Abkhaz Supreme Soviet, Valerian Kobakhia. The appeal called for Abkhazia to secede from Georgia and become either a separate union republic or part of the RSFSR. The local Georgian population of Abkhazia responded with counter-protests in the regional capital of Sukhumi, beginning on 25 March 1989. The Lykhny Appeal was also co-signed by the rector of the Abkhazian State University.
Ethnic Georgian students at the university announced plans for protests and called for the establishment of a separate branch for Georgian students in Abkhazia. The Georgian government approved the proposal by establishing a branch of Tbilisi State University in Sukhumi. Georgian anti-Soviet, pro-independence dissident groups claimed that the Soviet government, acting through the local Communist Party leadership, was using Abkhaz separatism to counter Georgian demands for independence from the Soviet Union. On 9 April, Soviet troops were deployed to Tbilisi and dispersed demonstrations calling for Georgian independence, resulting in casualties.
The 9 April tragedy and the storming of the building housing the Sukhumi branch of Tbilisi State University by armed Abkhazians eventually led to the first clashes between representatives of the Abkhaz and Georgian populations, which took place in Sukhumi on 16–17 July 1989. The resulting civil unrest quickly escalated into armed confrontations that, according to official accounts, left 18 people dead and at least 448 wounded, 302 of them Georgians. In response, Interior Ministry troops were deployed to quell the unrest.
Mikhail Gorbachev, who faced pressure from hardliners within the Communist Party of the Soviet Union who blamed him for the "loss of Eastern Europe", as well as from Soviet republics demanding independence, opposed the secession of any Soviet territory from the USSR. The Law on Secession was passed in April 1990 in an attempt to establish a legal mechanism for a right that had existed on paper under the Soviet Constitution, while simultaneously making the secession process more difficult. The law specified the procedures that Soviet republics had to follow to secede from the Soviet Union, while also granting autonomous republics and other regions the right to remain in the USSR. This increased the potential cost of secession for the union republics by creating the possibility that they could lose territory. Under Gorbachev, the Kremlin encouraged Abkhaz separatists as part of a divide-and-rule strategy to undermine stability in Georgia and weaken its national independence movement.
By July 1990, as neither side considered itself strong enough to resolve the dispute militarily, Georgian-Abkhaz tensions became largely confined to the legislatures, turning Abkhazia into a legal battleground and what was described as a "war of laws" until armed hostilities broke out in August 1992. In December 1990, the Abkhaz Supreme Soviet elected Vladislav Ardzinba, a member of the hardline Soyuz faction in the Congress of People's Deputies of the Soviet Union, as its chairman.
Ardzinba, a charismatic but excitable figure who was popular among Abkhazians, was believed by Georgians to have helped instigate the violence of July 1989. Ardzinba subsequently reneged on pre-election promises to increase Georgian representation in Abkhazia's autonomous institutions and sought to rule Abkhazia relatively single-handedly. For the time being, however, he avoided open conflict with the central authorities in Tbilisi.
Georgia boycotted the 17 March 1991 all-Union referendum on the preservation of the Soviet Union proposed by Mikhail Gorbachev. In Abkhazia, however, 52.3% of the population, comprising almost all of the ethnic non-Georgian population, participated in the referendum, with 98.6% voting to preserve the Union. Most ethnic non-Georgians in Abkhazia subsequently boycotted the 31 March referendum on Georgia's independence, which was supported by an overwhelming majority of the Georgian population. Within weeks, Georgia declared independence from the Soviet Union on 9 April 1991 under former Soviet dissident Zviad Gamsakhurdia.
In an effort to reach a compromise, Georgian President Zviad Gamsakhurdia negotiated electoral law reforms in August 1991 that granted the Abkhaz significant over-representation in the local Abkhazian Supreme Soviet, despite Georgians comprising 46% of Abkhazia's population and Abkhazians only 18%. Under the ethnic quotas introduced ahead of the 1991 elections, the 65 seats were allocated with 28 to Abkhazians, 26 to Georgians, and the remaining 11 to other ethnic groups. A two-thirds majority was required to pass "important legislation", ensuring that key decisions could not be adopted without the support of both Abkhaz and Georgian deputies and, in principle, giving each side veto power. The elections to the Abkhazian Supreme Soviet under this system were held in late 1991 and were the first multi-party elections in Abkhazia in 69 years. However, the Supreme Soviet soon became polarized between its ethnic Abkhaz chairman, Vladislav Ardzinba, and its ethnic Georgian first deputy chairman, Tamaz Nadareishvili.
Ardzinba created the Abkhazian National Guard that was mono-ethnically Abkhaz, and initiated a practice of replacing ethnic Georgians in leading positions with Abkhaz. He used the civil war that began with the overthrow of Gamsakhurdia in Georgia to pursue Abkhazia's separation, repealing numerous Georgian laws in Abkhazia and placing local enterprises and organizations, including the military and police, under regional jurisdiction.
The power-sharing agreement negotiated in 1991 soon proved unsustainable. Tensions escalated on 24 June 1992 when Abkhaz armed formations broke into the office of the ethnic Georgian Minister of Internal Affairs of Abkhazia, Givi Lominadze, beat him, and forcibly removed him from office, replacing him with an Abkhaz candidate who was appointed without the consent of the Georgian deputies of the Abkhaz Supreme Soviet. In June 1992, Ardzinba submitted a draft treaty proposing a federative/confederative arrangement to the ruling Georgian State Council. It was rejected by the Georgian leadership. The federative/confederative treaty proposed by Ardzinba declared Abkhazia to be a sovereign state and a "full-fledged participant in international and external economic relations". It further provided that Georgia and Abkhazia would "recognize each other as sovereign states", mutually recognize each other's territorial integrity, and refrain from "interfering in each other's internal affairs". The treaty also stipulated that Abkhazia would have the authority to conclude treaties independently with other states, republics of the Russian Federation, and members of the Commonwealth of Independent States (CIS); that Abkhazian law would take precedence within its territory; and that Georgia and Abkhazia would each possess separate citizenships, with dual citizenship permitted on the basis of a bilateral interstate agreement. The Georgian side opposed these provisions and rejected the proposal, arguing that it had been drafted without the participation of Georgian deputies. Georgians viewed the draft treaty as an attempt to disguise the division of the country into two sovereign states under the guise of a federation, maintaining that Abkhazia already possessed a significant degree of autonomy within Georgia, while the treaty went beyond autonomy and instituted a separate statehood.