Dumfriesshire, Clydesdale and Tweeddale (UK Parliament constituency)

Dumfriesshire, Clydesdale and Tweeddale is a constituency of the House of Commons, located in the South of Scotland, within the Dumfries and Galloway, South Lanarkshire and Scottish Borders council areas. It elects one Member of Parliament (MP) at least once every five years using the First-past-the-post system of voting. It is currently represented in Westminster by the former Secretary of State for Scotland, David Mundell, a Conservative, who has been the MP since 2005.

The seat has a diverse electoral history, with the Dumfriesshire area being a longtime Conservative seat, the Clydesdale area being formerly safe Labour territory, and Tweeddale had been part of Liberal Democrat-voting constituencies since the 1980s. Former Scottish Secretary, David Mundell has held the seat since 2005, and from 2005 to 2017 was the only Conservative MP in Scotland.

Constituency profile
One of the largest seats in terms of area, the constituency is predominantly rural and is very sparsely populated. It stretches from 10 miles outside of Edinburgh in the northeast all the way down to Gretna at the border with England. It is also the only seat in Scotland that has been held by the Conservatives in every election since its creation. It contains some very affluent areas as well as some more working-class areas; however, it is a large rural seat where farming is a big source of employment. The M74, which is the main road between Scotland and England, runs through the constituency as do the West Coast Mainline and Glasgow South Western railway lines. Its largest towns are Dumfries (Most of which is within the neighbouring seat of Dumfries and Galloway), Annan, Biggar, Gretna/Gretna Green, Langholm, Lockerbie, Moffat and Peebles. The seat also contains the Southern Upland Way, a popular walk for tourists in the south of Scotland. David Mundell has held the seat since its creation in 2005; however, it has been challenged by both the Labour Party and now the SNP. In the 2015 election, Mundell only retained the seat by a very slim majority of 798 with the SNP close behind. In the 2017 election, Mundell increased his majority to over 9000; however, by 2019 his majority had been reduced to 3800.

Boundaries
The Dumfriesshire, Clydesdale and Tweeddale constituency was created by the Fifth Review of the Boundary Commission for Scotland, and covers parts of the Dumfries and Galloway, South Lanarkshire and Scottish Borders council areas.

2005-2024: The Dumfries and Galloway Council wards of Annandale East and Eskdale, Annandale North, Annandale South, Lochar (part), Mid and Upper Nithsdale, and Nith (part), the Scottish Borders Council wards of Tweeddale East and Tweeddale West (part), and the South Lanarkshire Council wards of Clydesdale East and Clydesdale South (part).

2024-present: As above with some boundary changes within the Clydesdale East, Lochar and Nith wards.

Political history
The seat's main predecessor seats, Dumfriesshire, Clydesdale and Tweeddale, Ettrick & Lauderdale, all had distinct political influences. Dumfriesshire had been a Conservative/National Liberal seat from 1931 to 1997, but was lost to Labour's Russell Brown at the 1997 general election, in which the Conservatives lost all their Scottish seats.

Clydesdale had been a safe Labour seat since the 1980s, and Tweeddale, Ettrick and Lauderdale had been a Liberal/Liberal Democrat seat since 1983.

Following the boundary review for the 2005 general election, Labour held a clear majority of 12% over the Conservatives, according to calculations of notional results (an estimate of how the seat would have voted if it had existed at the previous election) and the seat was 96th on the Conservatives' target list. The Liberal Democrats finished in a close third place at the election. However, former Conservative MSP David Mundell was successful in gaining the seat from Labour, with a swing of 8.0%. This left him as the sole Conservative MP representing a Scottish constituency at the 2005 general election, after the Conservative MP for Galloway and Upper Nithsdale, Peter Duncan was defeated when standing at the new Dumfries and Galloway constituency, and Conservative attempts to gain Angus from the SNP ended in failure.

In 2010, Mundell was re-elected, with an increased majority. In 2015, after the SNP landslide victory in Scotland, he narrowly defeated the SNP candidate, Emma Harper by 798 votes, and was the only Scottish Conservative MP elected. However, following the SNP's losses at the 2017 snap general election, the Conservatives gained 12 seats in Scotland, with Mundell increasing his majority to 9,441 votes. Mundell was re-elected at the 2019 general election, but with a reduced majority, in an election where the SNP made gains across Scotland at the expense of Labour and the Conservatives.