shock therapy solutions were often dictated by Western consultants, of whom Jeffrey Sachs was best known but also most criticized. The striking electoral victory of Solidarity candidates in the limited elections, and the subsequent formation of the first non-communist government in the region in decades, encouraged many similar peaceful transitions from communist party rule in Central and Eastern Europe in the second half of 1989. In December 1989, changes to the Polish constitution were made, officially eliminating the "socialist" order: Marxist references were removed and the name of the country was changed back to the Polish Republic. Wałęsa, president of the Solidarity trade union, demanded early presidential elections. He was acting against the advice of his traditional Solidarity allies, intellectuals who were now running the government. Under pressure from the continuing worker unrest, Wałęsa declared himself a supporter of workers' interests, allegedly threatened by those whom he identified as communists (such as President Jaruzelski), or elitist political liberals (such as Prime Minister Mazowiecki). Wałęsa presented himself as a person of good conservative, Christian and nationalist credentials. In 1990, Jaruzelski resigned as Poland's president and was succeeded by Wałęsa, who won the 1990 presidential election. Lech Wałęsa's inauguration as president took place on 22 December 1990. He distanced himself from Wojciech Jaruzelski by accepting the prewar presidential insignia from President-in-Exile Ryszard Kaczorowski, who was stepping down. Wałęsa defeated Mazowiecki and in the second round Stanisław Tymiński, but under his presidency economic policy remained unchanged. The historically communist Polish United Workers' Party dissolved itself in 1990 and transformed into the Social Democracy of the Republic of Poland. The German–Polish Border Treaty, signed in November 1990, resolved the sensitive for Prime Minister Mazowiecki and his government issue of recognition of Poland's western border by Germany, after the country's unification. The Warsaw Pact was formally dissolved on 1 July 1991; the Soviet Union ceased to exist in December 1991 and the last post-Soviet troops left Poland in September 1993. On 27 October 1991, the first (since the 1920s) entirely free Polish parliamentary election took place. This completed Poland's transition from a communist party rule to a Western-style liberal democratic political system. See also Former eastern territories of Germany and Recovered Territories Cursed soldiers Polish People's Republic Administrative division of the Polish People's Republic Education in the Polish People's Republic Culture in the Polish People's Republic History of Solidarity Notes a.The troops were brought in