He was a radical writer - unafraid to speak his mind or attack injustice wherever he perceived it.

Harold Pinter, who died of cancer on Christmas Eve, aged 78, was one of Britain's greatest post-war playwrights. He revolutionised 20th-century theatre with his barbed politics and brooding portrayals of domestic life.

Traversing the worlds of cinema and stage, he produced classics for both that have stood the test of time.

But his talents extended beyond play-writing. He was an actor, poet, screenwriter and director - as well as having a passion for cricket.

His private life made headlines when, in 1980, he married historian Lady Antonia Fraser, whose first major work was a biography of Mary Queen of Scots, which she wrote while living on Eilean Aigas, the island in the River Beauly.

He had left his first wife, actress Vivien Merchant, for Lady Antonia. Soon after they split, Merchant died of alcoholism. Their son, Daniel, effectively disowned his father and Pinter was stricken with guilt at his first wife's death.

Professionally, his plays, which were first staged in the late 1950s, were renowned for their cool, menacing pauses.

A politically conscious man, he declined former Conservative prime minister John Major's offer of a knighthood and strongly attacked ex-Labour leader Tony Blair when Nato bombed Serbia.

The writer also criticised the invasion of Iraq as "a bandit act, an act of blatant state terrorism, demonstrating absolute contempt for the conception of international law".

He won many awards for his plays, the greatest of which was the Nobel Prize for Literature in 2005.

He wrote more than 25 plays and around a dozen film scripts. His first piece, The Room, contained many of the elements that would characterise his later works - namely a commonplace situation gradually invested with menace and mystery through the deliberate omission of an explanation or motivation for the action.

He once said: "How can you write a happy play? Drama is about conflict and degrees of perturbation, disarray. I've never been able to write a happy play, but I've been able to enjoy a happy life."

The writer was probably best known for his absurdist masterpieces The Caretaker, The Homecoming and Betrayal.

An introverted only child of immigrant Jews, he was raised as part of a large extended family in east London, but his childhood was interrupted by the outbreak of the war when he was evacuated to Cornwall. The separation from his parents, while traumatic, proved another source for his imagination and introspection.

He was 14 before he returned to London, by which point he had developed a love of the works of Franz Kafka and Ernest Hemingway.

His first love was acting and he accepted a grant to study at London's Royal Academy of Dramatic Arts. But his heart was not in his studies and, two years later, he left.

Demonstrating his refusal to conform, he was fined in 1949 for refusing to complete his National Service. Expressing his relief, he said: "I could have gone to prison - I took my toothbrush to the trials - but the magistrate was slightly sympathetic."

By 1950, Pinter had begun publishing poetry, but continued to appear on the stage until 1957, the same year The Room was published.

His first full-length play, The Birthday Party, was produced the following year in the West End. Despite closing after just one week to disastrous reviews, Pinter continued to write.

It was his second full-length play, 1960's The Caretaker, that secured Pinter's reputation as one of the country's foremost dramatists. Five years later, The Homecoming was published. It won a host of awards.

Pinter, who received the CBE in 1966, also wrote extensively for the cinema. His film work included The Servant (1963) and adaptations of F Scott Fitzgerald's The Last Tycoon (1974) and John Fowles's The French Lieutenant's Woman (1981).

From the 1980s onwards, he wrote only around half a dozen plays. But in 1995, when he received the David Cohen Literature Prize for lifetime achievement, Pinter summed up his career. "Quite simply, my writing life has been one of relish, challenge, excitement," he said.

In March 2005, Pinter appeared to suggest he had written his last play. "I think I've written 29 plays. Isn't that enough? I think it's enough for me. I've found other forms now," he said.

He had also been throwing his speech-writing skills into more political use. He raged against Blair, calling the ex-prime minister a "deluded idiot" and US President George Bush a "mass murderer".

In 2002, Pinter was diagnosed with cancer of the oesophagus, the same year he was appointed a Companion of Honour. Earlier this month, he was due to pick up an honorary degree from the Central School of Speech and Drama in London, but was forced to withdraw from the event because of illness.