Captain Sir Ion Hamilton Benn, 1st Baronet CB DSO (31 March 1863 – 12 August 1961) was a British politician and businessman. He was a Conservative member of parliament from 1910 to 1922
In 1900, he was elected to Greenwich Borough Council and served as mayor from 1901 to 1902. He was a founder member of the Metropolitan Water Board in 1903
Member of the Municipal Reform Party elected to the 1907 London County Council representing Greenwich.
Benn was once again a member of the London County Council from 1937 to 1946. He served on the Thames Conservancy Board from 1937 to 1946, and was a director of the Port of London Authority from its foundation in 1909 until February 1961, when he was 97.
More information on the Wikipedia page [1], and here.
Painting here [2].