Greene was a prolific and acclaimed author

Writer Sir John Mortimer joined a special gathering on Saturday to mark the centenary of the birth of British author Graham Greene.

Sir John was a guest speaker at Greene's former school, Berkhamsted Collegiate in Hertfordshire.

The event is one of several Greene tributes this year, following the author's death in 1991, aged 86.

Greene's acclaimed and often controversial works include Brighton Rock and The Third Man.

Other events being held to celebrate Greene's life and work include an exhibition of memorabilia at the British Library in London.

The show highlights the topics that fascinated Greene and gave him rich material for his books, such as espionage, alcoholism and travel.

John Mortimer is helping to mark the centenary

A stage musical of Greene's seaside thriller Brighton Rock will open at London's Almeida Theatre on 5 October.

It has been directed by Michael Attenborough, whose father Richard starred in the 1947 film of the novel.

Norman Sherry, a professor at Trinity University, San Antonio, Texas has also published the third and final volume of his biography, The Life of Graham Greene.

Moral conflict
Greene wrote his first novel The Man Within while at The Times. He later left his job to work as a full-time writer.

His love for travel was often reflected in his books. For example, a trip to Mexico led to his writing The Power and The Glory.

Vietnam, the Belgian Congo, Cuba, Kenya and Haiti were some of the other places he visited.

Greene's novel The Third Man was made into a classic movie

Greene's works also include The End of the Affair, The Quiet American, Our Man in Havana and Travels With My Aunt.

Many of his novels explore the conflict between faith and desire and politics and morality.

His books also often feature a stiff-upper lipped Briton trying to cope with extreme situations and exotic locations.

His stories have proved popular with movie directors, who have made feature films from titles such as The Quiet American, which starred Sir Michael Caine and Brendan Fraser.

Greene had a colourful personal life. He worked as a British secret agent in West Africa during World War II.

And he had a string of extra-marital affairs and socialised with some of the most famous figures of his time, including TS Eliot, Evelyn Waugh, Ian Fleming, and Noel Coward.

Amongst many interests, The Graham Greene Birthplace Trust can be found at www.grahamgreenebt.org