The Reichspräsident was the Germanhead of state under the Weimar constitution, which was officially in force from 1919 to 1945. In English he was usually simply referred to as the President of Germany. The German title Reichspräsident literally means President of the Reich.
The Weimar constitution created a semi-presidential system in which power was divided between the president, a cabinet and a parliament. The Reichspräsident was directly elected under universal adult suffrage for a seven-year term. It was intended that the president would rule in conjunction with the Reichstag (legislature) and that his emergency powers would be exercised only in extraordinary circumstances, but the political instability of the Weimar period, and a paralysing factionalism in the legislature, meant that the president came to occupy a position of considerable power (not unlike that of the German Emperor he replaced), capable of legislating by decree and appointing and dismissing governments at will.
In 1934, after the death of President Hindenburg, Adolf Hitler, already Chancellor, assumed the Presidency, but did not usually use the title of President – ostensibly out of respect for Hindenburg – and preferred to rule as Führer und Reichskanzler ("Leader and Reich Chancellor"), highlighting the positions he already held in party and government. In his last will in April 1945, Hitler named Joseph Goebbels his successor as Chancellor but named Karl Dönitz as Reichspräsident, thus reviving the individual office for a short while until the German surrender.
AHans Luther, Chancellor of Germany, was acting head of state of Germany from 28 February 1925 to 12 March 1925.
BWalter Simons, President of the Supreme Court of Germany, was acting head of state of Germany from 12 March 1925 to 12 May 1925.
CAdolf Hitler was served as Führer (the office position mergence of President and Chancellor) of Germany from 2 August 1934 to 30 April 1945.
Upon Generalfeldmarschall von Hindenburg's death, Adolf Hitler merged the offices of Chancellor and head of state in his person. He styled himself Führer und Reichskanzler ("Leader and Chancellor"), but did not use the title of Reichspräsident. Upon his suicide on 30 April 1945, Hitler nominated GroßadmiralKarl Dönitz to be President. Dönitz was arrested on 23 May 1945 and the office was dissolved.