Sydney E. Ahlstrom

Sydney Eckman Ahlstrom (December 16, 1919 – July 3, 1984) was an American historian. He was a Yale University professor and a specialist in the religious history of the United States.

Ahlstrom was born on December 16, 1919, in Cokato, Minnesota, the son of Joseph T. Ahlstrom (1878–1942) and Selma (Eckman) Ahlstrom (1881–1976), who were Swedish-American Lutherans. He graduated from Gustavus Adolphus College in St. Peter, Minnesota, with a Bachelor of Arts degree in 1941, and served in the US Army during the Second World War. He earned a master's degree at the University of Minnesota in 1946 and a Doctor of Philosophy degree at Harvard University in 1952. He was a Fulbright fellow at the University of Strasbourg, France, and an instructor at Harvard before joining Yale in 1954.

In 1973, he received the National Book Award in category Philosophy and Religion for A Religious History of the American People (1972).

He was elected a fellow of the American Academy of Arts and Sciences in 1978. In 1979, he was awarded the Christian Century Award for the Decade's Most Outstanding Book on Religion.

At the time of his retirement from Yale in 1984, he held the position of Samuel Knight Professor of American History and Modern Religious History. He died on July 3, 1984, in New Haven, Connecticut.