Gustav Walter Heinemann (ˈɡʊsta(ː)f ˈhaɪnəman; 23 July 1899 – 7 July 1976) was a German politician who was President of West Germany from 1969 to 1974. He served as mayor of Essen from 1946 to 1949, West German Minister of the Interior from 1949 to 1950, and Minister of Justice from 1966 to 1969.
Heinemann was named after his mother's father, a master roof tiler in Barmen, with radical-democratic, left-liberal, and patriotic views. His maternal grandfather, Heinemann's great-grandfather, had taken part in the Revolution of 1848. His father, Otto Heinemann, a manager at the Krupp steelworks in Essen, shared his father-in-law's views. In his youth, Gustav already felt called upon to preserve and promote the liberal and democratic traditions of 1848. Throughout his life, he fought against all kinds of subservience. This attitude helped him to maintain his intellectual independence even in the face of majorities in political parties and in the Church.
Having finished his elite secondary education in 1917, Heinemann briefly became a soldier in the First World War, but his severe illness stopped him from being sent to the front.
From 1918, Heinemann studied law, economics, and history at the universities of Münster, Marburg, Munich, Göttingen, and Berlin, graduating in 1922 and passing the bar in 1926. He received a Ph.D in 1922 and a doctorate of law in 1929.
The friendships that Heinemann formed during his student years often lasted for a lifetime. Among his friends were such different people as Wilhelm Röpke, who was to become one of the leading figures of economic liberalism, Ernst Lemmer, later a trade unionist and also a Christian Democrat, and Viktor Agartz, a Marxist.
At the beginning of his career, Heinemann joined a renowned firm of solicitors in Essen. In 1929, he published a book about legal questions in the medical profession. From 1929 to 1949, he worked as a legal adviser to the Rheinische Stahlwerke in Essen, and from 1936 to 1949, he was also one of its directors.