Under which US President did Henry Kissinger become National Security Adviser?

Henry Alfred Kissinger (born Heinz Alfred Kissinger, May 27, 1923) is an American statesman, political scientist, diplomat and geopolitical consultant. A Jewish refugee who fled Nazi Germany with his family in 1938, he became National Security Advisor in 1969 and United States Secretary of State in 1973. For his actions negotiating a ceasefire in Vietnam, Kissinger received the 1973 Nobel Peace Prize under controversial circumstances, with two members of the committee resigning in protest. Kissinger later sought, unsuccessfully, to return the prize after the ceasefire failed.

Kissinger served as National Security Advisor and Secretary of State under President Richard Nixon, and continued as Secretary of State under Nixon's successor Gerald Ford. On Nixon's last full day in office, in the meeting where he informed Ford of his intention to resign the next day, he advised Ford that he felt it was very important that he keep Kissinger in his new administration, to which Ford agreed.