Her political career began in 1999 when she was created a life peer as Baroness Ashton of Upholland, of St Albans in the County of Hertfordshire,[2] by Tony Blair's Labour government.

[4] In December 2009, she became the inaugural High Representative of the Union for Foreign Affairs and Security Policy that was created by the Treaty of Lisbon.

[5] Despite being criticised by some, particularly at the time of her appointment and in the early stages of her term of office, for her limited previous experience of international diplomacy, Ashton subsequently won praise for her work as a negotiator in difficult international situations, in particular for her role in bringing Serbia and Kosovo to an agreement in April 2013 that normalised their ties, and in the P5+1 talks with Iran which led to the November 2013 Geneva interim agreement on the Iranian nuclear programme.

[10][11][12][13][14] Between 1977 and 1983, Ashton worked for the Campaign for Nuclear Disarmament (CND) as an administrator and in 1982 was elected as its national treasurer and subsequently as one of its vice-chairs.

Having initially pushed for former British Prime Minister Tony Blair to become President of the European Council, Gordon Brown eventually relented on the condition that the post of High Representative be awarded to a Briton.

The magazine credited her, however, with piloting the Lisbon Treaty through the House of Lords, handling the European Commission's Trade Portfolio without disagreement with her colleagues, and being suited to consensus-building.

Nile Gardiner of The Heritage Foundation, who opposed a European Union role in foreign and security policy on principle,[38] wrote in The Daily Telegraph "This may well be the most ridiculous appointment in EU history".

[39] Daniel Hannan, a British Conservative MEP, complained that she had "no background in trade issues at a time when the EU is engaged in critical negotiations with Canada, Korea and the WTO".

[40] The Guardian quoted an anonymous Whitehall source as commenting "Cathy just got lucky...The appointment of her and Herman Van Rompuy European Council president was a complete disgrace.

[42][43] Notable events of her term included: In April 2013, after two years of negotiations, the governments of Serbia and Kosovo reached agreement to normalise their relations.

A cross-party committee of the U.S. House of Representatives nominated Ashton and her fellow negotiators Dacic and Thaci for the Nobel Peace Prize.

[57] A similar nomination came from the Group of the Progressive Alliance of Socialists and Democrats in the European Parliament[58] After the November 2013 negotiation of an interim agreement with Iran over its nuclear programme, the Financial Times wrote that Ashton was "no longer the diplomatic dilettante".

She said she was impressed by the "determination of Ukrainians demonstrating for the European perspective of their country" and observed "with sadness that police used force to remove peaceful people from the center of Kyiv...

[55] Subsequently, Russian Deputy Prime Minister Dmitry Rogozin criticised Ashton's categorisation of the anti-government protests in Kyiv as peaceful in nature, pointing to the death of a number of police officers.

In the call, Paet said he had been told by a woman doctor named Olga that snipers responsible for killing police and civilians in Kyiv last month were protest movement provocateurs rather than supporters of then-president Viktor Yanukovych.

"[61] The woman doctor, Olga Bogomolets, said in an interview reported by Paul Waldie of The Globe and Mail that, in her conversation with the Estonian minister, "she did not indicate that protesters used snipers.

Ashton expressed concern at the new law "potentially penalizing contacts with foreign nationals with up to 20 years in prison" and reducing "the burden of proof for charges of treason and espionage".

[65][66] Ashton was questioned by Members of the European Parliament in 2009 about her role as national treasurer in the British Campaign for Nuclear Disarmament in the 1980s, amid claims by its opponents that it may have had financial links to the Soviet Union.

The survey, carried out by lobbying and PR company Burson-Marsteller, asked 324 Brussels policy-makers to rate the European Commissioners with a grade of A to E (A being the highest).

Her spokesman stated that her remark had been "grossly distorted" and that she had also referenced Israeli victims in Sderot, but this fact had been omitted from the original transcript.

Ashton's staff also pointed to her personal involvement in nuclear negotiations with Iran as among the international responsibilities that had kept her away from Commission meetings.

[79] The Polish Minister for European and Economic Affairs, Mikolaj Dowgielewicz, stated in 2011 that criticism of Ashton was "a lot of hot air" and that "she has an impossible job to do and she is doing it well.

The tone of public comment on Ashton's performance in office was subsequently to be influenced especially by her contributions to negotiations over Kosovo and Iran.

That makes her an ideal negotiator", says Alexander Graf Lamsdorff, the head of Germany's business-friendly Free Democratic Party (FDP) in the European Parliament and a member of its Committee on Foreign Affairs.

In September 2013, Peter Oborne, the chief political commentator of The Daily Telegraph, wrote:Well, let's admit we were all completely wrong.

It takes little imagination to envisage how a male politician from any of the main parties would have exploited the Kosovo peace-deal, or the Morsi visit.

[83] In July 2014, as discussions took place on the selection of Ashton's successor, Paul Taylor of Reuters wrote in The New York Times, as part of a larger critique of the political nature of appointments to the European Commission:While Ms. Ashton had some successes, brokering a first accord between Serbia and Kosovo and leading negotiations for an interim nuclear deal between Iran and world powers, critics say she has too often been missing in action closer to home.

[84]Reflecting on her record, in July 2014, Adam Boulton in the UK's Sunday Times concluded: As the European Union's high representative for foreign affairs and security policy, Catherine Ashton still bestrides the international stage four years after Gordon Brown, the man who gave her the job, was expelled from the corridors of power.

She was a surprise nominee to everyone including herself, and few would have expected then that her successor as Britain's commissioner would struggle to match Baroness Ashton in calibre and clout.