I became a writer for the most traditional of reasons: someone offered me an advance. My supervisor at Cambridge, Professor Geoffrey Elton, was asked by a publisher to recommend someone to write An Atlas of Irish History and he suggested me. I was and am permanently short of money, so I agreed instantly.

The Atlas was well received, so I was offered an advance to write a biography of Patrick Pearse, the leader of the Irish rebellion of 1916 (Patrick Pearse: the triumph of failure). It was through this that I discovered I loved writing biography, not least because it taught me so much about how to detach myself and get into someone else's mind. I signed up to write about Victor Gollancz, the publisher and campaigner, and then realised that since his papers were all in an archive in the University of Warwick, I had to choose between being a writer or a civil servant. I chose insecurity.

Gollancz was a huge project, which taught me inter alia about Judaism, communism, the 1930s and the clash between idealism and pragmatism. I've learned a great deal too from my brief books about a British prime minister (Harold Macmillan: a life in pictures) and a socialist revolutionary (James Connolly) and most from the biggest and fattest of my books, The Pursuit of Reason: The Economist, 1843-1993. That was a book that required me to get a grasp of international economics and politics as well as of the thought processes of the journalists and managers who kept the soul of the paper intact over one-and-a-half centuries. It stretched my brain almost to cracking point, but it was a wonderful education.

Like all my previous non-fiction books, my book on the Orange Order (and similar organisations) - The Faithful Tribe: an intimate portrait of the loyal institutions - was suggested by someone else. I had spent a great deal of time at Orange parades and come to know many decent people in the Orange Order at a time when they were being vilified and reviled throughout the world because of the media coverage of Drumcree and their own hopelessness with public relations. At lunch with a publisher to discuss an entirely different project, I went on about Drumcree so much that he said, 'You should be writing a book about the Orange Order; you're obsessed with it.' So I did.

I become obsessed with all my non-fiction books (which feed into my crime fiction - e.g. aspects of The Economist that feature in Publish and be Murdered).

		Another preoccupation that, for reasons too complicated to go into, had been bubbling for several years, was finally published in 2005. Newspapermen: Hugh Cudlipp, Cecil Harmsworth King and the glory days of Fleet Street is a joint biography of two people - Cecil King and Hugh Cudlipp - who together were responsible for turning the Mirror into the biggest selling newspaper in the world (5,500,000 circulation) as well as for founding a great newspaper empire. Their backgrounds were dramatically different: Cudlipp became a journalist at 14 whilst King, the nephew of Lord Northcliffe and Lord Rothermere, was educated at Winchester and Oxford. They ended their careers as Lord Cudlipp and Mr King. It is a story of old Fleet Street, of the bonding of two opposites, of patricide (for Cudlipp, the protégé, had to sack King, his mentor), of the strange role of King's second wife, the extraordinary Dame Ruth Railton and of lots more. Its writing was another education.

2005 also saw the publication of the third edition of An Atlas of Irish History.

In March 2006 my biography of Patrick Pearse, Patrick Pearse - the triumph of failure was reissued by the Irish Academic Press.