[3] On 13 October 1886 Lowther was made lieutenant in the 3rd Battalion, The Border Regiment (The Royal Cumberland Militia).
[4] Soon thereafter, he was appointed a deputy lieutenant in the counties his family had traditionally dominated, Cumberland (21 November 1891[5]) and Westmorland (26 January 1892[6]).
[10] In 1944, he finally succeeded to the Earldom of Lonsdale on the death of his childless brother, Hugh.
Hugh's free-spending, sporting life had largely wrecked the estate, and he was forced to auction off the contents of Lowther Castle in 1947.
[11] On 24 April 1889, Lonsdale married Gwendoline Sophia Alice Sheffield (born 1869, died 4 November 1921), daughter of Sir Robert Sheffield, 5th Baronet, with whom he had three children:[12] His first wife, Gwendoline, having died in 1921, Lonsdale married Sybil Beatrix Feetham on 8 October 1923.