Italian playwright Dario Fo, who won the Nobel Prize for Literature, has died at the age of 90.
Italian PM Matteo Renzi said his country had lost one of the leading protagonists of Italian culture and civil life.
"His satire, research, scenography and artistic activity will leave the inheritance of a great Italian to the world," he said.
Mr Fo, whose energetic mocking of Italian political life, social mores and religion won him the Nobel Prize, died in Milan's Luigi Sacco hospital, a spokeswoman said.
The author of Accidental Death of An Anarchist and more than 70 other plays saw himself in the role of the jester, combining raunchy humour and satire.
He was admired and reviled in equal measure. His political activities saw him banned from the United States and censored on Italian television, and his flamboyant artistic antics resulted in repeated arrests.
In recent years, Mr Fo became a point of reference for Italy's anti-establishment 5-Star Movement, which has paid tribute to him as a "spiritual guide".
Movement leader Beppe Grillo posted a video of an appearance by Mr Fo at a 2013 rally giving impetus to the movement to shake up Italy's paralysed political system.
"Do it yourselves, please. Do it yourselves," he exhorted. "Please, turn everything upside down."
The son of a railway worker and farm hand, Mr Fo had an early introduction to narrative traditions through his grandfather, a well-known storyteller.
He studied painting at Milan's prestigious Brera Academy as well as architecture and, at age 25, he began to write and perform satirical cabarets at the Piccolo Theatre in Milan.
A staunch leftist, Mr Fo founded a theatre company with his wife, the late actress Franca Rame, later a senator. Ms Rame died in 2013 at the age of 84.
The pair made a career out of mocking post-war Italy, ranging from the domestic terrorism of the late 1970s to the bitter debates over abortion and divorce, and a political corruption scandal in the 1990s.
Dealing with subjects such as the Vietnam War, the Chinese revolution and student revolts in the West, Mr Fo and Ms Rame took their works out of "bourgeois" theatres and into streets, piazzas, occupied factories and circus-style tents.
Italian bishops struggled with Mr Fo's freewheeling interpretations of the Catholic faith.
His one-man show was seen by an estimated one million people when it toured Italy over 18 months in 1968-1970.
As his work grew more radical, Mr Fo fell out of favour with state TV, which banned him for more than decade. Prosecutors failed to convict him of offending institutions such as the national police force.
Some suggested right-wing sympathisers among the police were behind the kidnapping and rape of Mr Fo's wife by Italian neo-fascists on a Milan street in 1973, when society was rent between extreme right and left.
Not long after winning his Nobel, Mr Fo wrote to Italy's president demanding justice in the case, even though statutes of limitations had expired.
Motivating him, Mr Fo said, was not a thirst for revenge but a desire to help the country recognise the barbarities of that period and move on.
Accidental Death Of An Anarchist drew from an event that continues to divide Italians, who are often split between left and right in a legacy of the battles between fascists and communists during the Second World War.
The play is based on the fall from a police station window of an anarchist who was being questioned over a 1969 Milan bank bombing. The police officer who led the interrogation was shot dead in 1972.
Mr Fo's stature as an artist began to outstrip his fame as a militant by the end of the 1970s. Milan's La Scala let him direct a play, Story Of A Soldier, in 1978 and audiences flocked to his works in mainstream theatres.
Still, in 1980 he and Ms Rame were refused visas to the United States because of their support for left-wing activities in Italy.
The decision sparked controversy and prompted US intellectuals to stage protests in support. In 1984, the US government relented and allowed the couple to visit New York to see a production of Accidental Death Of An Anarchist.
The Nobel Prize for literature came in 1997. The citation described Mr Fo as a writer "who emulates the jesters of the Middle Ages in scourging authority and upholding the dignity of the downtrodden".
Guests attending his prize lecture in Stockholm in 1997 had a surprise as they opened their texts. Instead of printed paragraphs, they found 25 pages of coloured drawings, with scattered words: "Provocation... ignorance of our times."
While he enraged the Vatican, Mr Fo once ended up on the same side as the Catholic Church, when both lobbied vigorously - but unsuccessfully - to stop the 2000 execution in Virginia of Rocco Derek Barnabei, a US citizen of Italian origin.
Mr Fo pledged to donate some of the proceeds of his theatre work to anti-death penalty causes around the world. Even though the husband-wife team snubbed the bourgeois theatre at times, it made their plays sold-out successes, notably a 2003 spoof of then-Italian premier Silvio Berlusconi, The Two-Headed Anomaly.
That play, at one of Rome's mainstream theatres, explored what many contended was the conflict of interest posed by a premier who was at the time also Italy's richest man, thanks to vast business holdings, largely in the media sector.
The work asked the question: what would happen if half of Russian president Vladimir Putin's brain was used to replace half of Mr Berlusconi's brain?
The play also pre-shadowed Mr Berlusconi's real-life split with his second wife amid sex scandals. While Mr Fo had fun with politicians' foibles, his own foray in politics was a failure.
In 2006, he lost a bid in a primary to become the centre-left's candidate for mayor of Milan.
Mr Fo and Ms Rame had a son, Jacopo Fo, also a writer.