Kurt Rosenfeld (1 February 1877 – 25 September 1943) was a German lawyer and politician (SPD). He was a member of the national parliament ("Reichstag") between 1920 and 1932.
Kurt Samuel Rosenfeld was born at Marienwerder, a mid-sized town near Danzig, then in East Prussia. Between 1896 and 1899 he studied jurisprudence and at Freiburg (where one of his teachers was Max Weber), then moving on to Berlin from where he emerged in 1905 with a doctorate in law. After this he took a job as a lawyer in Berlin. While still a student he joined the Social Democratic Party ("Sozialdemokratische Partei Deutschlands" / SPD), and between 1910 and 1920 he served as a Berlin city councillor. For most of this time he was on the left wing of the SPD. He was also building a reputation as a trial lawyer: during this period he defended in court like minded political comrades including Rosa Luxemburg, Kurt Eisner und Georg Ledebour. Other left wing Berlin politicians in his circle included Clara Zetkin, Karl Liebknecht, Franz Mehring, Karl Radek and Anton Pannekoek.
Between 5 August 1914 and 9 November 1918 Kurt Rosenfeld took part in the First World War as a soldier. He was nevertheless one of those in the SPD who had opposed the party leadership's 1914 decision to agree a political truce at the outbreak of the war and, more specifically, to vote in favour of "war credits". As the scale of the human slaughter on the front line and of the economic destitution on the home front mounted, the number of SPD politicians opposing the war increased, and it was primarily over this issue that the party split in 1917. Rosenfeld was among those who formed the breakaway faction, which now became the Independent Social Democratic Party of Germany ("Unabhängige Sozialdemokratische Partei Deutschlands" / USPD).