Altschul was born in 1920 in Manhattan to Helen Lehman Goodhart (maternal granddaughter of Mayer Lehman, one of the three founding brothers of Lehman brothers) and Frank Altschul, an investment banker who was a senior partner at Lazard Frères until 1945 and chairman of General Investors Corporation until he retired in 1961.
He graduated from Deerfield Academy in Massachusetts and in 1943 from Yale College.
He served in the Marines from 1943 through 1945 and was a New York Times reporter in the late 1940s. As he had family connections to the Lehman family, he worked as an analyst with Lehman Brothers before joining General American Investors Company (a closed-end investment concern in which his family has a substantial interest) and then Goldman Sachs where he served as a general partner from 1959 to 1977 and a limited partner from 1977 to 1999. He was also chairman of General American Investors from 1961 to 1995.
He led the private family office, Overbrook Management Corporation, founded by his father to manage and protect the wealth and financial well-being of the Altschul Family.
In 2002, the office opened its doors to provides asset management and related services to institutional investors and high Netto worth individuals. Altschul was on the Board of Trustees of many museums and philanthropic organisations, including the Whitney Museum, the United Jewish Appeal, the Overbrook Foundation, the Metropolitan Museum of Art, The American Assembly, and the International Foundation for Art Research.
Barnard College at its 1984 commencement ceremonies awarded Altschul its highest honor, the Barnard Medal of Distinction. Siri von Reis (divorced 1972) with whom he had three children:
Serena Altschul (b 1970), Music Television and Cable News Network broadcast journalist
Diana Landreth Childs (divorced)
Patricia Dey, married in 1996.
Trustee American Assembly. Former chairman board trustees Barnard College. Member governing board Yale University Art Gallery, 1987-1996.
Member chairman's council Metropolitan Museum Art. Council member National Trust for History Preservation. Former chairman board International Foundation for Art Research 1st lieutenant United States Marine Corps Reserve, 1943-1945.
Member Council Foreign Relations.
Married Patricia Madelyn Dey. Children from previous marriages: Stephen Frank, Charles, Arthur G. Junior, Emily Helen, Serena von Reis. 1 step-son, Whitney Sudler Smith.
