In the 1720s, members of the Grosvenor family, began the development of Grosvenor Square as the centrepiece of the Grosvenor Estate. Originally surrounded by gates and railings, with access limited to local residents who held keys and paid for its upkeep, Grosvenor Square garden was designed as an oval enclosure. This layout was simplified in the 19th and 20th centuries when London plane trees were introduced.
During the Second World War, the Square and surrounding area was severely damaged and in the early 1940s the iron railings were removed to support the war effort.
As part of the peacetime celebrations in 1946, it was decided to make Grosvenor Square a public space for everyone's enjoyment. The Ministry of Works took over its upkeep, a role fulfilled today by The Royal Parks.
Since the 1930s the Square has had a strong association with the USA, and in 1938 The American Embassy was established at 1 Grosvenor Square. In 1948 the British memorial to President Roosevelt was unveiled, and in 1985 the Eagle Squadron monument was erected along the same central axis.
On the 13th April 1994 the Prime Minister, Rt. Hon. John Major MP, unveiled a commemorative stone to honour the 50th anniversary of the D-Day landings in Normandy on the 6th June 1944.