Mikhail Gorbachev, the last Soviet leader, died on Tuesday at a Moscow hospital. He was 91. The Central Clinical Hospital said in a statement that Gorbachev died after a long illness. No other details were given. Gorbachev won the 1990 Nobel Peace Prize for his role in ending the Cold War. He set out to revitalize the Soviet Union but ended up unleashing forces that led to the collapse of communism and the breakup of the state.