Philipp Heinrich Scheidemann was a German politician of the Social Democratic Party of Germany (SPD). In the first quarter of the 20th century, he played a leading role in both his party and in the young Weimar Republic. During the German Revolution of 1918–1919 that broke out after Germany's defeat in World War I, Scheidemann proclaimed a German Republic from a balcony of the Reichstag building. In 1919, he was elected Reich Minister President by the National Assembly meeting in Weimar to write a constitution for the republic. He resigned the office the same year due to a lack of unanimity in the cabinet on whether or not to accept the terms of the Treaty of Versailles.