George de Mohrenschildt (April 17, 1911 – March 29, 1977) was a petroleum geologist and professor who befriended Lee Harvey Oswald in the summer of 1962 and maintained that friendship until Oswald's death, two days after the assassination of U.S. President John F. Kennedy. He was acquainted with the Bush family; George H. W. Bush had roomed with de Mohrenschildt's nephew, Edward G. Hooker, at Phillips Academy in Andover, Massachusetts. He was also acquainted with the Bouvier family, including Jacqueline Bouvier Kennedy, the president's wife, when she was still a child. His testimony before the Warren Commission investigating the assassination was one of the longest of any witness.
Read more about George De Mohrenschildt: Early Life, Dallas, Oswald and Haiti, Later Life and Death, Another Backyard Photo, Memoir, Depictions in The Popular Media