Paul Theodor Uhlenhuth (7 January 1870 in Hanover – 13 December 1957 in Freiburg im Breisgau) was a German bacteriologist and immunologist, and Professor at the University of Strasbourg (1911–1918), at the University of Marburg (1918–1923) and at the University of Freiburg (1923–1936). He was a rector of the University of Freiburg from 1928 to 1929. After his retirement in 1936, he led his own research institute in Freiburg, known as the State Research Laboratory, until his death in 1957.
He is famous in the annals of forensic science for developing the species precipitin test, known as the Uhlenhuth test, which could distinguish human blood from animal blood in 1901, a discovery which had tremendous importance in criminal justice in the 20th century. In 1915, he discovered the pathogen of Weil's disease. He also invented the arsenic treatment of syphilis and the antimony treatment of many tropical diseases, and was an influential promoter of cancer research. He was a recipient of numerous honours, and was a member of the Academy of Sciences Leopoldina and the Royal Swedish Academy of Sciences. He was nominated for the Nobel Prize in Medicine 40 times between 1910 and 1952, notably by Nobel laureate Karl Landsteiner. At the time of his death, he was one of the most celebrated medical researchers in Germany, and one of the rare examples of someone who was equally celebrated in the west and east during the Cold War.
