Mikołajczyk, Stanislaus (stänēsˈläs mēkôwĪˈchĭk) [key], 1901–66, Polish politician and leader of the Polish Peasant party. After the German conquest of Poland, he became vice premier (1941) and premier (1943) in the Polish government in exile at London. He sought to reach agreement with the USSR concerning the Polish-Russian border and with the Polish Committee of National Liberation (see Lublin) concerning the future Polish government. After the Yalta Conference he joined the new Polish government as vice premier and minister of agriculture. He soon was the only center of opposition to the Communist and left-wing Socialist leaders of the state, and the procedure adopted in the elections of 1947 resulted in his defeat. Midołajczyk fled and settled in the United States. He remained active in the politics of Polish exiles.