Aleksei Kaledin, USSR Cossack commander. Don Cossack. Graduated from the Academy of the General Staff, 1889. Cossack commander during World War I. Cavalry general, 1917. Elected Ataman of the Don Cossacks, 1917. Began the opposition to communist rule on the Don. Committed suicide when it became clear that his initiative was not receiving enough support. His death became the signal for the widespread involvement of the Don Cossacks in the anticommunist struggle during the Civil War.
Director of the Institute for Lake Studies of the Academy of Sciences of the USSR, 1955. President of the USSR Geographical Society, 1964. Vice-president of the International Geographical Union, 1968-1972.
Regarded as one of the most outstanding modern glaciologists.