A chance encounter in a Paris museum led to eminent historian Simon Schama paying a visit to an Edgware school last Thursday.

Professor Schama, famous for his acclaimed BBC2 television series History of Britain, which he wrote and presented, came to North London Collegiate School, in Canons Drive, where he talked about his new book, Rough Crossings: Britain, the Slaves and the American Revolution. The event was organised by students who run the school's history society after spotting him in a Parisian museum.

Sixth-former Caroline Silbe said: "We were in Paris on a school trip when we bumped into him in a musuem and got talking. We then emailed him and invited him to come to speak at the school."

The historian a former pupil of Haberdashers' Aske's School, in Elstree spoke about his new work which tells the story of the struggle for freedom in the 1770s and 1780s by thousands of black loyalists'. These were slaves who, lured by the promise of freedom made by the British, rebelled against their masters and decided they wanted to fight for Britain during the war of American Independence.

The professor of art history at Columbia University, in New York, said: "There is an assumption that freedom began in America when the British left. But some chose the other side and this is an inconvenient fact for America's grand narrative. I have an American friend who said he loved the book and looked forward to visiting me in Guantanamo Bay."

Prof Schama's History of Britain show was acclaimed for his ability to discuss history in an engaging and original way. At the school, his easy manner was on display as he peppered his talk with jokes.

When headteacher Bernice McCabe walked in late, he made the audience laugh by saying: "I see the headmistress is late yet again," and when a teacher asked him if his book should be compulsory reading for the Ku Klux Klan, he replied: "My wife would think not. She wants me to be around for a while."

A question and answer session followed the talk and students were also able to have their copies of the book signed.