Because of its geographical location and the absence of any naturally secure borders, Belarus often has been a battleground among more powerful countries and an important east–west trade route between Europe and Russia. After the fall of Kievan Rus' in 1240, most of the territory of what is now Belarus fell under Polish and then Lithuanian influence. Russia absorbed the area during the partitions of Poland in the eighteenth century and formalized it as the so-called "pale of settlement" for Jews in the Russian empire.
Because the region's economy could not support the burgeoning population and because of the tsarist government's restrictions on Jews, more than 1.5 million Jews and Belarusians fled to the United States and to the Russian Far East in the 50 years preceding the 1917 Russian Revolution.
Like so much of the Russian borderlands, Belarus was the site of major fighting during World War I and the Russian Civil War, with Red, White, Polish, and some indigenous Belarusian forces all playing a role. In 1922, Belarus became one of the founders of the Union of Soviet Socialist Republics and began to assume its current borders. Those were enlarged in 1924, at the expense of Ukraine and Russia, and further increased after the Molotov-Ribbentrop Treaty in 1939, at the expense of Poland.
Under the Soviets, Belarus was subjected to intense Russification and seldom represented a challenge to Moscow's policies. But in the 1980s that situation began to change: a Belarusian People's Front was organized, albeit with its initial headquarters in Vilnius, Lithuania, after the Chernobyl nuclear accident contaminated much of Belarusian territory. Adding to a nationalist upsurge was the discovery of mass graves from the Stalinist terror of the 1930s at Kuropaty and other locations.
Along with other republics of the former Soviet Union, Belarus held competitive elections for a new Parliament in March 1990, but significantly, the conservative Communists dominated that body. Nonetheless, in response to the nationalist Popular Front, the Parliament declared Belarus a sovereign state within the USSR in July 1990. At the time of the August 1991 coup in Moscow, the leader of the Belarusian Parliament backed the coup leaders: he was subsequently deposed and Belarus declared its independence. His replacement, Stanislav Shushkevich, a nuclear scientist who had helped expose the consequences of Chernobyl, led Belarus toward independence via the CIS.
But if Shushkevich was a reformer, Belarus's prime minister Vyacheslav Kebich was not. A longtime Communist Party functionary, he resisted change, rejected efforts to have a referendum on early elections, and ultimately led the Parliament in deposing Shushkevich. In March 1994, the Parliament adopted a new constitution to replace the Sovietera one. This document created the position of president as chief of state and called for elections, which were held on 10 July 1994. In these elections, Aleksandr Lukashenko unexpectedly triumphed, winning 80% of the vote on an anticorruption and pro-Russian platform. Two years later, Lukashenko proposed constitutional reforms that disbanded the sitting Parliament, creating a bicameral body chosen in controversial elections in November 1996. In addition, Lukashenko extended his own presidential term—which was to have ended in 1999—until 2001. Throughout the latter half of the 1990s, Belarus pursued political and economic union with Russia. Various agreements were signed by the two countries and are on their way to implementation.