[1] Clifford took part in the Crimean war, where he received the appointment of aide-de-camp to Sir George Brown, commanding the light division, and was present at Alma and Inkerman, and for his gallantry in the latter battle was decorated with the Victoria Cross, by leading one of the charges, killing one of the enemy with his sword, disabling another and saving the life of a soldier (5 November 1854).

[2] In May 1855, Clifford was appointed deputy assistant quartermaster-general, and remaining in the Crimea until the conclusion of the war was then promoted to the rank of brevet major, and received the medal and clasps for Alma, Inkerman, and Sebastopol, and from foreign governments the Legion of Honour and the 5th class of the Medjidie.

[1] On the outbreak of hostilities in China Clifford sailed thither, and as assistant quartermaster-general was present at the operations between December 1857 and January 1858 which resulted in the capture of Canton.

Early in 1879, Clifford was selected to proceed to South Africa to take charge of the communications of Lord Chelmsford between Durban and the forces in the field.

[1] Clifford married, 21 March 1857 in Dublin, Josephine Elizabeth, the only surviving child of Joseph Anstice of Madeley Wood, Shropshire, a professor at King's College London.