He was voted Germany's most popular politician, a chisel-jawed, gelled-haired aristocrat who held such rock-star status that his party used to play an AC/DC track every time he took to the stage. But Karl-Theodor zu Guttenberg has resigned as defence minister after being engulfed by a plagiarism scandal, leaving the ruling coalition with a serious charisma vacuum. 
 
 His departure is a huge blow for Chancellor Angela Merkel and her Christian Democratic Union party (CDU). Already weakened after defeats in recent regional elections, she is facing the prospect of implosion at six other local polls this year. 
 
 The 39-year-old baron, often tipped to be a future chancellor, has handed in his notice to Merkel after almost two weeks of frontpage stories about the authenticity of his PhD thesis. He is now expected to retreat to his castle in Bavaria to plot his next move. "It is the most painful step I've ever had to take," Guttenberg said at a press conference in Berlin. "I was always prepared to fight but I have reached the limits of my powers." 
 
 Last week the University of Bayreuth stripped Guttenberg of his doctorate after he admitted substantially copying (inadvertently, he said) from other sources. He blamed the errors on his busy schedule: when he finished his thesis in 2006, he was juggling his duties as an MP and raising two daughters with his TV presenter wife, the equally blue-blooded Countess Stephanie von Bismarck. The admission led to him being dubbed the minister for cut-and-paste, or Baron zu Googleberg. 
 
 Merkel admitted she was caught off guard by the resignation, saying she was "surprised" when she received a request from Guttenberg to talk to her over the phone . She said she accepted his resignation "with a heavy heart" and praised Guttenberg as someone with an "exceptional political talent". It was too early to name a successor, she added, but a decision would be made shortly. 
 
 Before the scandal broke last month, Guttenberg was often described as the "shooting star" of conservatism in Germany. He built a reputation as a plain-speaking man of action in a brief stint as economy minister and then, after the 2009 election, as defence minister. 
 
 Good-looking and apparently fearless, he would swoop in to visit German troops in Afghanistan looking like an extra from Top Gun in aviator shades, flight suit and desert boots. These visits received breathless write-ups in Germany's multimillion-selling tabloid Bild, and pictures were splashed over gossip magazines. 
 
 A new biography of Guttenberg, published on Tuesday, recalls how the dashing minister even had his own theme tune, Hell's Bells by the Australian rock band AC/DC, which would herald his arrival at events hosted by the CDU or its Bavarian sister party, the CSU. 
 
 The book, Guttenberg Biographie, describes its subject as "Germany's number one celeb" and recalls how he had such presence that when he walked through a crowd he was like "Moses parting the Red Sea". 
 
 In less than two years as defence minister, Guttenberg pushed through the most drastic reform of Germany's armed forces since the second world war. Most notably, he successfully fought for a plan to end conscription, part of an effort to slim down the German military and make it better adapted to an era in which it faces growing demands to deploy overseas. 
 
 In his resignation speech, he insisted the reforms would continue. It was wrong that he had become the story, overshadowing the deaths and woundings of 13 Bundeswehr soldiers last week, he said. " I will gladly concede to my opponents that I was appoined minister for defence, not self-defence," he said. 
 
 But however much praise he received for his bold decision-making in office, Guttenberg's crisis management after the plagiarism allegations emerged two weeks ago was less impressive. 
 
 He issued a statement describing them as "absurd", then said he would stop using his title as a doctor only temporarily while Bayreuth University looked into the accusations. He told jeering lawmakers last week that he "did not deliberately cheat, but made serious errors". Merkel stood by Guttenberg, saying a week ago that she appointed him as defence minister, not as an academic assistant. 
 
 But the scandal wouldn't go away, raising the possibility that Guttenberg would be a liability rather than an asset in forthcoming state elections. 
 
 "I think that, if this had carried on longer … it could have done more damage than would making a clean cut now and looking forward," said Oskar Niedermayer, a political science professor at Berlin's Free University. 
 
 Many commentators believe Guttenberg will rise again. Merkel herself refused to rule out a comeback, telling reporters she was confident that she would have the opportunity to work with Guttenberg again in the future. Referring to his resignation phone call, she said: "That certainly won't be the last time he and I have a personal conversation." 
 
 It's all in the name 
 
 One of the German media's favourite facts about the now former defence minister is his quite spectacular name. When he was born on 5 December 1971, the politician was christened Karl-Theodor Maria Nikolaus Johann Jacob Philipp Franz Sylvester Joseph von und zu Guttenberg. The last bit means "baron of Guttenberg", a village in the Franken area of Bavaria where the Guttenbergs have had their family seat – an impressive castle – since 1315. 
 
 His friends in politics preferred to call him simply K-T but his many enemies never tired of rolling out his freight train of a monicker to remind everyone of their rival's noble background. 
 
 Despite his privileged upbringing – or perhaps because of it – Guttenberg was hugely popular with the tabloid Bild newspaper, which rarely referred to him without mentioning that he was "Germany's most popular politician" – an honour he received via a poll in 2009, when he took the top spot from Angela Merkel. He was also referred to as the "German Kennedy", with his stylish TV presenter wife inevitably described as his "Jackie O". 
 
 But over the past two weeks, Guttenberg has received yet more nicknames, most notably Baron zu Googleberg, the minister for cut and paste. 

 Germany's Defence Minister Karl-Theodor zu Guttenberg caved in to overwhelming public and political pressure and announced his resignation yesterday after weeks of criticism over revelations that he plagiarised his doctoral thesis. 
 
 The aristocratic conservative had been considered Germany's most popular politician and was viewed as a future chancellor. His resignation came as a major blow to Chancellor Angela Merkel who had been counting on his support in regional elections this year. 
 
 In the semi-theatrical style which has become the hallmark of the 39-year-old baron's brief yet flamboyant political career, Mr zu Guttenberg called a press conference at the Berlin defence ministry to announce with tears in his eyes that his resignation was "the most painful decision in my life". 
 
 Thanking Ms Merkel, who 24 hours earlier was still supporting her Defence Minister to the hilt, he added: "I was always ready to fight, but I have to admit that I have reached the limit of my strength." The Berlin chancellery issued a statement saying Ms Merkel had accepted his resignation "with a heavy heart". 
 
 Mr zu Guttenberg stepped down after an unprecedented 50,000 German academics and their supporters signed an open letter to Ms Merkel protesting about his plagiarism. They said it made a "mockery" of the country's long-established reputation for academic and scientific integrity. 
 
 The letter was delivered a fortnight after a leading academic published damning evidence which showed that Mr zu Guttenberg had copied more than half of his 475-page Bayreuth University doctorate from other people's work without attributing the sources. The thesis was published in 2006. 
 
 Oliver Lepsius, a law professor at Bayreuth University who succeeded Mr zu Guttenberg's doctoral supervisor, said: "We have been taken by a fraud. His brazenness in deceiving honourable university staff was unique." 
 
 Mr zu Guttenberg initially dismissed the allegations as "absurd" and Ms Merkel suggested his offences were not significant as she had recruited him to serve as Defence Minister and not as an academic. However last week Mr zu Guttenberg sought to end the affair and save his job by renouncing his doctorate and admitting that he had made a terrible mistake. 
 
 But conservative support for the minister had all but evaporated by yesterday amid mounting allegations that sections of his other publications had also been plagiarised. Mr zu Guttenberg was nicknamed "Baron cut and paste" and "zu Googleberg" in the media. Norbert Lammert, the conservative parliamentary leader said his plagiarism was "a nail in the coffin for democracy". 
 
 Opposition parties attacked Ms Merkel for her handling of the affair. Thomas Oppermann, the Social Democrats' parliamentary leader, said her decision to continue backing Mr zu Guttenberg in the face of overwhelming evidence that he had cheated over his PhD was a disgrace. "She has brought shame on the reputation of politics," he said. 
 
 Mr zu Guttenberg's resignation could hardly have come at a worse time for the Chancellor. There is no obvious choice for a successor. Yet her Defence Minister is leaving as the German armed forces begin their most significant reforms since the end of the Second World War. These involve axing conscription and creating a fully professional army while maintaining an unpopular presence in Afghanistan. 
 
 At the same time, Ms Merkel's party faces a total of eight key regional and local elections during this so-called "super-election" year. Their outcome will determine her ability to survive as Chancellor. 
 
 Ms Merkel's Christian Democrats face their next electoral test in the eastern state of Saxony Anhalt but their most crucial challenge will be in southern Baden-Württemberg at the end of March. The southern state has been conservative-controlled for more than 50 years, but opinion polls suggest the party could lose to Greens and Social Democrats for the first time. 
 
 Observers predict that if the conservatives lose the state, Ms Merkel may be forced to call an early general election ahead of its scheduled date in September 2013. 
 
 It was not clear if Mr zu Guttenberg would stay on as a backbench MP. Several observers said he could easily return to politics within two years. 
 
 Plagiarising Politicians 
 
 Joe Biden A string of plagiarism and falsification charges forced the current US Vice President, above, to abandon his own race for the presidency in 1987. Biden's fall from grace began when he delivered a speech on his humble background, which plainly lifted a paragraph almost word-for-word from a speech the British Labour politician Neil Kinnock had delivered earlier that year. Allegations later emerged that Biden had also copied speech material from fellow politicians Robert Kennedy and Hubert Humphrey, and admitted to having received an "F" grade during law school for plagiarising a published report in one of his essays. Within a month of copying Kinnock's speech, he had dropped his campaign for the1988 presidential elections. 
 
 George Bush Pakistani journalist Ahmed Rashid alleged that the former US President's autobiography Decision Points borrowed heavily from his own work when it was released in November last year. One news organisation also drew close parallels between the memoir and passages from the investigative journalist Bob Woodward's book Bush at War, as well as a work by former US press secretary Ari Fleischer. At the time, Bush's publisher responded to the allegations by saying that any resemblances between Bush's book and other works only confirmed its accuracy. 
 
 Saif al-Islam Gaddafi The London School of Economics confirmed yesterday that it is investigating allegations that Colonel Gaddafi's son plagiarised his PhD thesis whilst studying at the university from 2003 to 2008. The Libyan dictator's son is accused of using the services of a ghost writer and copying large sections of his final essay, which he completed as part of a doctorate qualification. The LSE is also under pressure to return £300,000 from the Gaddafi International Charity and Development Foundation, which was part of a £1.5m donation pledged by Saif al-Islam in 2009. 
 
 Gordon Brown During his three years in power, the former British prime minister was regularly blasted in the blogosphere for echoing the words of his prominent contemporaries just that little bit to closely – particularly those across the pond in America. Close comparisons have been drawn between his speeches and those of former American vice president Al Gore, former president Bill Clinton and former Secretary of State Colin Powell, which some believe to be rooted in Brown's admiration for the wordsmithery of the prominent American political consultant Robert Shrum.
– Germany's aristocratic defense minister has resigned after being caught in a plagiarism scandal. Tens of thousands of academics wrote to the government in protest after it was discovered that Baron Karl-Theodor zu Guttenberg—now nicknamed "Baron Cut and Paste" and "zu Googleberg"—had plagiarized large chunks of his PhD thesis, reports the Independent. Academics determined that Guttenberg had copied more than half of his 2006 thesis from other people's work without giving them credit. Resignation "is the most painful step I've ever had to take," said the 39-year-old baron, who is now expected to retreat to his castle in Bavaria to plan his next step, the Guardian notes. Before the scandal, Guttenberg was widely considered Germany's most popular politician, and he is expected to eventually return to politics.