Henry Berge Helson (June 2, 1927 - January 10, 2010) was an American mathematician at the University of California at Berkeley who worked on analysis.Helson received his bachelor's degree from Harvard University in 1947. With the support of a Harvard traveling fellowship, he spent the academic year 1947-1948 in Europe, he visited London, Paris, Prague, and Vienna, but spent most of his time in Warsaw and then from spring 1948 in Wroclaw, where he worked with Marczewski. Helson received his Ph.D. in 1950 from Harvard with supervisor Lynn Loomis and then spent the academic year 1950-1951 primarily in Uppsala working with Beurling but with frequent trips elsewhere in Europe. He became in 1951 an instructor and then an assistant professor at Yale University. He became in 1955 an assistant professor, in 1958 an associate professor, and in 1961 a full professor at the University of California, Berkeley, retiring there as professor emeritus in 1993. In 1970 he was an Invited Speaker at the ICM in Nice.