29 April (11 May) 1857 in Tsarskoe Selo in a family of Russian Emperor Alexander II was born the fourth son, Grand Duke Sergey Alexandrovich, Russian statesman and public figure.
On April 28 (May 11), 1912 the first issue of the Yermak newspaper was published in Tyumen. It was a progressive, non-partisan, literary, public newspaper, transformed from the newspaper Siberian Trade Intermediary. Yermak was published in Tyumen from April 28 (May 11), 1912 to April 29 (May 12), 1917.
On May 11, 1925, the All-Russian Congress of Soviets of Workers', Peasants', Cossacks' and Red Army deputies approved the revised text of the Constitution of the Russian Socialist Federal Soviet Republic, formalizing the new state-legal status of Russia as a union republic within the USSR.
On May 11, 1945 in the course of Prague Offensive (6-11 May 1945) the troops of the 1st, 2nd and 4th Ukrainian fronts completed the liberation of Czechoslovakia.