Antoni Zygmund was born on December 25, 1900 in Warsaw, in what is now Poland but at the time was part of the Russian empire. He received a doctoral degree in mathematics from the University of Warsaw in 1923. Zygmund taught at Polytechnic School of Warsaw and later at the University of Vilnius, Lithuania.
At the beginning of World War II, Zygmund was drafted into the Polish army. He escaped with his family from German controlled Poland and moved the United States in 1940. He accepted a position at the University of Chicago in 1947, where he remained until his retirement in 1980. Zygmund received the National Medal of Science in 1986.
Zygmund made important contributions in analysis, particularly measure theory and integration. He is significant in the history of probability because of his contributions to the theory of stochastic integration. Many of his books remain classics: Trigonometric Series (1935), Analytic Functions (1938), Measure and Integral (1977).
Zygmund died on May 30, 1992 in Chicago, Illinois, USA.