David Emmanuel (31 January 1854 – 4 February 1941) was a Romanian Jewish mathematician and member of the Romanian Academy, considered to be the founder of the modern mathematics school in Romania.
Born in Bucharest, Emmanuel studied at Gheorghe Lazăr and Gheorghe Șincai high schools. In 1873 he went to Paris, where he received his Ph.D. in mathematics from the University of Paris (Sorbonne) in 1879 with a thesis on Study of abelian integrals of the third species, becoming the second Romanian to have a Ph.D. in mathematics from the Sorbonne (the first one was Spiru Haret). Emmanuel was the president of the first Congress of Romanian Mathematicians, held in 1929 in Cluj.
In 1882, Emmanuel became a professor of superior algebra and function theory at the Faculty of Sciences of the University of Bucharest. Here, in 1888, he held the first courses on group theory and on Galois theory. Among his students were Anton Davidoglu, Alexandru Froda, Traian Lalescu, Grigore Moisil, Miron Nicolescu, Octav Onicescu, Dimitrie Pompeiu, Simion Stoilow, and Gheorghe Țițeica. Emmanuel had an important role in the introduction of modern mathematics and of the rigorous approach to mathematics in Romania.