George III is shown wearing the uniform of a General Officer with the Garter Star on his coat, holding a walking stick in his right hand and a glove in the other. His bicorne hat includes the black Hanoverian cockade, and his red coat is decorated with the start of the Order of the Garter. Behind, his charger is held by a groom and in the distance is a troop of cavalry.

The portrait was painted for the King, probably in 1799-1800 at Windsor, and initially hung in the King's Dining Room at Kew along with a pendant of Queen Charlotte (RCIN 405423). Later it was installed on the Principal Staircase at Buckingham Palace, as part of Queen Victoria's dynastic hang, where it remains today.