 He then commanded 1st (Guards) Brigade, which was broken up in August 1915, and afterwards became Military Secretary at General Headquarters France.On 24 February 1916 he received the Légion d'honneur, class of "Commandeur", and in the Birthday Honours of 1918 he was appointed Knight Commander of the Order of St Michael and St George.Lowther was elected as Member of Parliament (MP) for Appleby at a by-election in 1915, but the constituency was abolished in 1918.