Blue plaque to Stanley Baldwin on Eaton Square on 18th October 2022 in London, United Kingdom. Stanley Baldwin was a British Conservative Party politician who served as prime minister on three occasions, from May 1923 to January 1924, from November 1924 to June 1929, and from June 1935 to May 1937. A blue plaque is a permanent sign installed in a public place in the United Kingdom and elsewhere to commemorate a link between that location and a famous person, event, or former building on the site, serving as a historical marker.