Prior to its uniform adoption of proportional representation

Proportional representation

Proportional representation is a concept in voting systems used to elect an assembly or council. PR means that the number of seats won by a party or group of candidates is proportionate to the number of votes received. For example, under a PR voting system if 30% of voters support a particular...

 in 1999, the United Kingdom

United Kingdom

The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...

 used first-past-the-post

Plurality voting system

The plurality voting system is a single-winner voting system often used to elect executive officers or to elect members of a legislative assembly which is based on single-member constituencies...

 for the European elections

Elections in the European Union

Elections to the Parliament of the European Union take place every five years by universal adult suffrage. 736 MEPs are elected to the European Parliament which has been directly elected since 1979. No other body is directly elected although the Council of the European Union and European Council is...

 in England

England

England is a country that is part of the United Kingdom. It shares land borders with Scotland to the north and Wales to the west; the Irish Sea is to the north west, the Celtic Sea to the south west, with the North Sea to the east and the English Channel to the south separating it from continental...

, Scotland

Scotland

Scotland is a country that is part of the United Kingdom. Occupying the northern third of the island of Great Britain, it shares a border with England to the south and is bounded by the North Sea to the east, the Atlantic Ocean to the north and west, and the North Channel and Irish Sea to the...

 and Wales

Wales

Wales is a country that is part of the United Kingdom and the island of Great Britain, bordered by England to its east and the Atlantic Ocean and Irish Sea to its west. It has a population of three million, and a total area of 20,779 km²...

. The European Parliament constituencies

European Parliament constituency

Members of the European Parliament are elected by the population of the member states of the European Union , divided into constituencies....

 used under that system were smaller than the later regional constituencies and only had one Member of the European Parliament

Member of the European Parliament

A Member of the European Parliament is a person who has been elected to the European Parliament. The name of MEPs differ in different languages, with terms such as europarliamentarian or eurodeputy being common in Romance language-speaking areas.When the European Parliament was first established,...

 each.

The constituency of Thames Valley was one of them.

When it was created in England in 1979, it consisted of the Westminster Parliament constituencies of Beaconsfield

Beaconsfield (UK Parliament constituency)

Beaconsfield is a county constituency represented in the House of Commons of the Parliament of the United Kingdom. It elects one Member of Parliament by the first past the post system of election. It is among the safest of Conservative seats....

, Chesham and Amersham, Eton and Slough

Eton and Slough (UK Parliament constituency)

Eton and Slough was a parliamentary constituency represented in the House of Commons of the Parliament of the United Kingdom. It elected one Member of Parliament by the first-past-the-post voting system....

, Spelthorne

Spelthorne (UK Parliament constituency)

-Elections in the 2000s:-Elections in the 1990s:-Elections in the 1980s:-Elections in the 1970s:-Elections in the 1960s:...

, Windsor and Maidenhead

Windsor and Maidenhead (UK Parliament constituency)

Windsor and Maidenhead was a county constituency in the Royal Borough of Windsor and Maidenhead in Berkshire. It returned one Member of Parliament to the House of Commons of the Parliament of the United Kingdom....

, Wokingham

Wokingham (UK Parliament constituency)

Wokingham is a parliamentary constituency represented in the House of Commons of the Parliament of the United Kingdom. It elects one Member of Parliament by the first past the post system of election.-Boundaries:...

 and Wycombe

Wycombe (UK Parliament constituency)

Wycombe is a parliamentary constituency represented in the House of Commons of the Parliament of the United Kingdom. It currently elects one Member of Parliament by the first-past-the-post system of elections....

. Following boundary changes which took effect for the 1984 election, the constituency lost the Beaconsfield, Eton, Chesham, Amersham and Wycombe areas to the new Oxfordshire and Buckinghamshire

Oxfordshire and Buckinghamshire (European Parliament constituency)

Prior to its uniform adoption of proportional representation in 1999, the United Kingdom used first-past-the-post for the European elections in England, Scotland and Wales...

 constituency, while gaining the town of Reading

Reading, Berkshire

Reading is a large town and unitary authority area in England. It is located in the Thames Valley at the confluence of the River Thames and River Kennet, and on both the Great Western Main Line railway and the M4 motorway, some west of London....

 in the form of the constituencies of Reading East and Reading West

Reading West (UK Parliament constituency)

Reading West is a county constituency represented in the House of Commons of the Parliament of the United Kingdom. Like all such constituencies, it elects one Member of Parliament by the first past the post system of election...

. The Westminster parliamentary constituency of East Berkshire which was created in 1983 was also part of Thames Valley. The constituency boundaries were then unchanged until the constituency was abolished in 1999.

Members of the European Parliament

Elected		Member	Party
	1979	Baroness Elles Diana Elles, Baroness Elles Diana Louie Elles, Baroness Elles was a barrister and United Nations representative from the United Kingdom. She was a delegate to the European Parliament for over a decade.-Early years:...	Conservative Conservative Party (UK) The Conservative Party, formally the Conservative and Unionist Party, is a centre-right political party in the United Kingdom that adheres to the philosophies of conservatism and British unionism. It is the largest political party in the UK, and is currently the largest single party in the House...
	1989	John Stevens John Stevens (politician) John Christopher Courtenay Stevens is an English politician. A Conservative Member of the European Parliament from 1989 to 1999, he contested the Buckingham constituency in the 2010 general election as an independent, against Commons speaker John Bercow.-Background:Stevens was educated at...	Conservative Conservative Party (UK) The Conservative Party, formally the Conservative and Unionist Party, is a centre-right political party in the United Kingdom that adheres to the philosophies of conservatism and British unionism. It is the largest political party in the UK, and is currently the largest single party in the House...
	1999	constituency abolished