Mielke became a member of the German Communist Party during the 1920s. In 1931 he took part, along with two fellow Communists, in the murder of a pair of Berlin police officers. Fleeing arrest for that crime, he escaped to the Soviet Union where he joined numerous other German Communist exiles in Moscow. Due to his record as a reliable Stalinist, Mielke survived Stalin's purges, which decimated the exile German community. From 1936 to 1939 he was sent to fight in the Spanish Civil War on the Communist side; during World War II he found himself caught in France, interned as an enemy alien by the Vichy government.
In 1945 Mielke was returned to Germany by the Soviet authorities, with a mandate to build up a security force which would ensure the dominance of the Communist Party in the Soviet occupation zone of Germany. He eventually rose to head the Ministry of State Security known as the Stasi, East Germany's equivalent of the Soviet KGB.
Mielke headed the Stasi from 1957 until the fall of the Berlin Wall in 1989. His network of 85,000 full-time domestic spies and 170,000 voluntary informers kept tabs on millions of people. At his orders and with his full knowledge, the East German secret police also engaged in arbitrary arrest, kidnapping, brutal harassment of political dissidents, and the inhumane imprisonment of tens of thousands of citizens. Mielke oversaw financial corruption on a very large scale, as well. He was one of the most powerful – and most hated – men in East Germany, feared even by members of his own Stasi.
After the fall of the Berlin Wall, Mielke was arrested by the new German authorities and charged with the murder of the police officers, but poor phyiscal and mental health allowed him to avoid a serious prison sentence.
Erich Mielke is buried in the Zentralfriedhof Friedrichsfelde in Berlin. But in a final snub reflecting how much he was despised by his fellow countrymen, his grave was kept out of the memorial where other famous communists were laid to rest. Mielke died on May 22 2000 aged 92 in an east Berlin nursing home. About 100 mourners reportedly attended the funeral. Mielke's grave is outside the memorial section established at the entrance in 1951 by East German leaders for communist heroes. Among those buried there are Karl Liebknecht and Rosa Luxemburg, co-founders of the German Communist Party who were arrested and killed by army irregulars in 1919, as well as one-time East German leaders Wilhelm Pieck and Walter Ulbricht.