Suave, good-looking and media-savvy, the 39-year-old aristocrat, who can trace his ancestry back to the 12th century, was named Germany's youngest-ever economy minister two years ago and was often mentioned as a future chancellor.
Karl-Theodor Maria Nikolaus Johann Jakob Philipp Franz Joseph Sylvester Baron von und zu Guttenberg, to give him his full name, or "KT" for short, was until very recently the darling of the media and public alike.
During the last election in 2009, he was dubbed the "Rocking Baron" or the "Cool Baron" for his love of rock music and apparent lack of pretension, drawing hysterical crowds to election rallies that invited comparisons to Barack Obama.
His youthful looks, slick gelled-back hair, trendy glasses and snappy fashion sense earned him front-page appearances not only in the mainstream media, but also in the glossy weeklies.
Together with his wife, the no less glamorous descendant of Otto von Bismarck, Germany's 19th century "Iron Chancellor" and father of the modern state, the pair formed the high-profile power couple.
And despite the aristocratic name and a castle in Bavaria's Franconia region, German voters flocked to the baron and he was credited with boosting the appeal of Chancellor Angela Merkel's often staid Christian Democrats (CDU) and their Bavarian conservative allies in Guttenberg's party the CSU.
Appointed defence minister in a post-election reshuffle in 2009, the tide began to turn as he came under fire for his handling of the aftermath of a deadly airstrike in Afghanistan that happened before he became minister.
A high-profile target, German papers then jumped on a series of minor scandals at the end of last year, beginning in November with an alleged mutiny on the naval training ship Gorch Fock.
Then in December he was accused of turning a visit to Afghanistan into a publicity stunt because he took with him not only his wife but also a television chatshow host and a battalion of photographers.
When he got back to Berlin he was pictured at an evening function cutting a dashing figure still in his battle fatigues, with his explanation that he had no time to change failing to convince suspicious commentators.
But it was "Copygate" that finally brought down the high-flyer.
Allegations surfaced in February that "Dr" zu Guttenberg had in fact copied large passages of his 475-page law thesis without proper attribution.
Smelling blood, the sharks moved in for the kill and the next few days saw the former pin-up of German politics widely ridiculed with nicknames like "Baron Cut-And-Paste" and "zu Googleberg."
In a botched announcement to selected media, causing a walk-out in protest from other journalists at a nearby government news conference, he said he would temporarily give up his "doctor" title, becoming plain old Baron zu Guttenberg.
But despite backing from Merkel and CSU party boss Horst Seehofer, the baron finally fell on his sword, depriving Merkel, who has six state elections to fight this year, of a key vote-winner.