George Sergius de Mohrenschildt (Russian: ??????? ????????? ?? ??????????; 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 US President John F.
Kennedy.
His testimony before the Warren Commission investigating the assassination was one of the longest of any witness.