He served as Member of Parliament for Brighton from 1906 to 1910, when he did not stand for re-election after disagreeing with government policy.

In recognition of this work during the First World War he was knighted as Knight Grand Cross of the Order of the British Empire (GBE) in the 1920 civilian war honours.

[1] Ridsdale married Susan Stirling, daughter of J. R. Findlater of Aberlour, Banffshire.

[1] His nephew, Sir Julian Ridsdale, was later the long-serving Conservative MP for Harwich.

This article about a Liberal Member of the Parliament of the United Kingdom representing an English constituency is a stub.