[4] After finishing college, he went to Poland on an inspection trip for the Joint Distribution Committee to study relief and rehabilitation in Eastern Europe.
In 1931, he became a partner of Kuhn, Loeb & Co.[5] In February 1942, during World War II, he was recommissioned to the United States Army as a major.
[6] He had an apartment in New York City, a house in Cos Cob, Connecticut, and a horse and cattle farm called Snake Hill in Middleburg, Virginia.
[3] In 1946, Warburg married Wilma M. Shannon, with New York Supreme Court Justice Charles W. Froessel performing the ceremony.
[8] Warburg died from heart disease at Memorial Hospital in Winchester, Virginia, near his farm Snake Hill, on July 10, 1973.