Gawain Robards was an Auror under the command of Rufus Scrimgeour during the Second Wizarding War. Following Cornelius Fudge's fall from power in 1996, Scrimgeour replaced Fudge as Minister for Magic, and as such Robards was promoted to replace Scrimgeour as Head of the Auror Office. Scrimgeour, during his attempts to convince Harry Potter to become the Ministry of Magic's new "poster boy", offered to set up an interview with Robards, knowing he cherished a desire to join the Auror department one day, in exchange for his cooperation. Harry, however, refused.
It is unknown who initially succeeded Robards as head of the Aurors, but he was eventually succeeded by Harry himself following the end of the war.