He retained the seat for three Parliaments, serving from 1929 to 1945. In the 1945 general election de Rothschild came third, the first time this had happened to any Liberal candidate in the constituency. It must have appeared that the days when the Isle seat was a Conservative/Liberal marginal had ended in 1945. The new Conservative MP, Harry Legge-Bourke, had a majority of 6.1% over Labour, with the Liberal almost 10% further behind. He retained the seat until his death in 1973, with Labour in second place. The Liberal Party did not contest general elections in 1951, 1955, 1959, 1964 and 1970. The Liberal vote in 1966 was only 11.4%. Clement Freud gained the seat for the Liberals from the Conservatives in a 1973 by-election during the height of the 1970s Liberal revival. He retained this seat until it was abolished in 1983; however, Freud surprisingly lost its successor seat in 1987. The constituency was renamed in 1983, with most of the territory incorporated into the constituency of North East Cambridgeshire. Boundaries In the Representation of the People Act 1918, the county constituency was defined as having the same boundaries as the administrative county of the Isle of Ely, which had been formed in 1889 from a traditional sub-division of the historic county of Cambridgeshire in East Anglia. The bulk of the constituency was formed from the abolished Wisbech Division of Cambridgeshire, with the northernmost parts of the abolished Chesterton and Newmarket Divisions, including the city of Ely. In 1965, the Isle of Ely county was merged into the new administrative county of Cambridgeshire and Isle of Ely and in the next redistribution of parliamentary seats, which took effect for the February 1974 general election, the constituency was defined as comprising the Municipal Borough of Wisbech; the urban districts of Chatteris, Ely, March, and Whittlesey; and the rural districts of Ely, North Witchford, and Wisbech. The only change was the loss of the small rural district of Thorney, which had been included in the new administrative county of Huntingdon and Peterborough and was now transferred to the borough constituency of Peterborough. Meanwhile, as a result of the Local Government Act 1972, the two counties of Cambridgeshire and Isle of Ely, and Huntingdon and Peterborough were merged to form the non-metropolitan county of Cambridgeshire, with effect from 1 April 1974. However, the next redistribution did not come into effect until the