Johnson was quickly sworn in as President on '' Air Force One '' in Dallas on November 22 , 1963 , just 2 hours and 8 minutes after John F. Kennedy was assassinated , amid suspicions of a conspiracy against the government . He was sworn in by U.S. District Judge Sarah T. Hughes , a family friend . In the rush , a Bible was not at hand , so Johnson took the oath of office using a Roman Catholic missal from President Kennedy 's desk . Cecil Stoughton 's iconic photograph of Johnson taking the presidential oath of office as Mrs. Kennedy looks on is the most famous photo ever taken aboard a presidential aircraft
John F. Kennedy was assassinated
Assassination of John F. Kennedy
Lyndon B. Johnson