The constituency was created in 1918 from the former seats of Westminster & Strand. From 1918 to 1950, it returned five Conservative MPs, with Labour and the Liberals having little support in the area.
After William Burdett-Coutts, the first MP for the seat, died in 1921 there was a by-election where all three candidates claimed to be anti-waste. At the time the Anti-Waste League was active. It was formed to advance the political ambitions of the newspaper owner Lord Rothermere. The objects of the League were to insist upon measures being taken to restore the country to solvency, urge a wholesale reduction of expenditure, fight the battle of local rates and oppose sham Anti-Waste candidates. The Conservative candidate John Nicholson won the election, but the Anti-Waste League (whose candidate later became a Conservative MP) polled respectably and the Liberal candidate (a former MP) came third.
After Nicholson's death in 1924 a further by-election took place. The new Conservative candidate Otho Nicholson was challenged by the prominent politician Winston Churchill as a Constitutionalist, the formidable Labour stalwart and future MP Fenner Brockway, and a little-known Liberal. The Constitutionalist label was one used by a number of candidates, mostly ex-Liberals like Churchill, in the 1920s. The Constitutionalists did not function as a party and most of them ended up joining the Liberal or Conservative Parties. Nicholson beat Churchill with a very small majority of 43.
By the 1945 general election, the electorate of the area had dropped by almost half since the pre-war by-election. Labour almost equalled the 27% vote Brockway had received in 1924. The Independent Progressive candidate of 1939 reappeared as a Communist candidate and received 17.6% of the vote. The Conservatives still had an absolute majority of the vote. For the 1950 general election, the seat became the central part of the new constituency of Cities of London and Westminster.