 From 1885 to 1918 the parliamentary borough of Boston returned one MP, while the Lincolnshire county division of Spalding, in the south-east of the historic county, elected another MP.In 1918 these two seats were merged to form this constituency.When created in 1918 the constituency had the same boundaries as the traditional sub-division of the historic county known as the Parts of Holland, which had become an administrative county in 1889.