Prior to the 1918 election the county of Kinross was covered, nominally, by Clackmannanshire and Kinross-shire, which also covered, nominally, the county of Clackmannan, and the county of Perth was covered, nominally, by Eastern Perthshire, Perth (as a burgh constituency) and Western Perthshire. Constituency boundaries were defined in terms of the Representation of the People (Scotland) Act 1832 and the Redistribution of Seats Act 1885[2] and, by these terms, five detached parishes of the county of Perth and one detached parish of the county of Stirling were within the Clackmannanshire and Kinross-shire constituency.[2] Also, by 1918, for local government purposes, under legislation dating from 1889, county boundaries throughout most of Scotland had been redrawn, and detached parishes had become generally historic.
The Representation of the People Act 1918 took account of new local government boundaries in definitions of new constituency boundaries, and the Kinross and Western Perthshire constituency was defined as covering the county of Kinross and the Central, Highland and Western districts of the county of Perth, including the county of Perth burghs of Aberfeldy, Auchterarder, Callander, Crieff, Doune and Dunblane.[2]
A by-election was held for this seat in 1938 after The Duchess of Atholl resigned her seat in opposition to Neville Chamberlain's policy of appeasement.
For the February 1974 general election, as a result of the Second Periodical Review of the Boundary Commission, there were minor alterations to the boundaries of the Kinross and West Perthshire constituency and the Perth and East Perthshire constituency. Kinross and West Perthshire was defined as covering the county of Kinross and the Central, Highland and Western districts of the county of Perth, including the county of Perth burghs of Aberfeldy, Auchterarder, Callander, Crieff, Doune, Dunblane and Pitlochry.[2]
February 1974 boundaries were used also in the general elections of October 1974 and 1979.
In 1975, under the Local Government (Scotland) Act 1973, counties and burghs throughout Scotland had been abolished in favour of regions and districts and islands council areas. The county of Kinross and most of the county of Perth had been merged into the Tayside region. The burghs of Callander, Doune, and Dunblane in the county of Perth, the Perth parish of Muckhart and the Western district of the county (except the electoral division of Ardoch) had been merged into the Central region.
New constituency boundaries, taking account of new local government boundaries, were adopted for the 1983 general election. Constituencies defined to cover the Tayside region included Perth and Kinross, and constituencies designed to cover the Central region included Stirling.
Another General Election was due to take place before the end of 1940. The political parties had been making preparations for that election and by autumn 1939, the following candidates had been selected: