Colonel Fiennes Stanley Wykeham Cornwallis, 1st Baron Cornwallis, CBE, TD, JP, DL (27 May 1864 – 26 September 1935) was a British Conservative politician.

[3] He was elected to the House of Commons as Member of Parliament for Maidstone in 1888, a seat he held until 1895 and again from 1898 to 1900.

He was appointed Honorary Colonel of the Thames and Medway Heavy Brigade, Royal Artillery, on 11 March 1933.

[6] Fiennes Wykeham Mann Cornwallis was killed in Ireland in May 1921 during the Irish War of Independence.

Lord Cornwallis was succeeded in the barony by his second son, Wykeham Stanley.