[1][2] Spencer was given command of the 44th Regiment of Foot in 1845 and, having been promoted to lieutenant colonel on 17 May 1854 and to colonel on 20 June 1854, he led that regiment at the Battle of Alma, at the Battle of Inkerman and at the Siege of Sevastopol during the Crimean War.

[2] Promoted to lieutenant general on 9 May 1868, he went on to be Commander-in-Chief of the Bombay Army in 1869 before retiring in 1875.

[5][6] The couple had five daughters and a son:[7][8] One of Spencer's grandsons was the Reverend Canon Henry Spencer Stephenson, Chaplain to King George VI and Queen Elizabeth II.

Sir Augustus Almeric Spencer, commander of the 44th Regiment of Foot, was awarded the French Legion of Honour that was reported in the Le Moniteur.

[13] Spencer died on 28 August 1893 and was buried at Brompton Cemetery in London.