The Representation of the People Act of 1918 (often referred to as the '1918 Reform Act' or, less frequently, the 'Fourth Reform Act') 1 was a landmark in modern British history and the most substantial and significant change in the composition of the political nation ever to take place. 2 The increase in the electorate was far larger than that of any previous measure, both numerically and proportionately, and the 1918 Reform Act marked a fundamental change in the principles upon which the franchise was based, one element of which was the admission of women to the parliamentary suffrage for the first time. 3 In essence, the vote became a matter of adult citizenship, although at first this was restricted for women by an age limit of 30 years and a basic property qualification, until a further measure in 1928 equalised the terms for both genders as simple residence and legal adulthood (which in this period was 21 years of age). The extent of the change can be measured by the proportion of the adult population registered as electors: this was 29. 4% in 1910, 79.5% in 1919, 90.9% in 1929, and 98.6% in 1939 (the latter increase being due to more thorough registration, not to any further change in the electoral system). 4 The greater scale of the 1918 Reform Act than any previous measure is shown in Table 1.1 This is unlike its predecessors -the First (also known as 'Great') Reform Act of 1832, the Second Reform Act of 1867, and the Third Reform Act of 1884 -which are almost always described in this way.2 For the general context of franchise extension from 1832 to 1918, see E.