[1] He should not be confused with Alexander L. (Sasha) Rosenberg, a Russian-American mathematician at Kansas State University.
His family escaped Nazi Germany in 1939, moving to Switzerland, to England, and then to Ontario, Canada.
[1][3] He completed his PhD in 1951 at the University of Chicago, with a doctoral thesis on ring theory supervised by Irving Kaplansky.
His students at Northwestern included Vera Pless, later to be known for her work in combinatorics and coding theory.
He moved to Cornell University in 1961, and served as department chair there from 1966 to 1969 where his PhD students included Vera Pless, Lindsay Childs and David Dobbs.