In the middle of the 17th century, Britain was devastated by a civil war that divided the nation into two tribes - the Roundheads and the Cavaliers. In this programme, celebrities and historians reveal that modern Britain is still defined by the battle between the two tribes. The Cavaliers represent a Britain of panache, pleasure and individuality. They are confronted by the Roundheads, who stand for modesty, discipline, equality and state intervention. The ideas which emerged 350 years ago shaped our democracy, civil liberties and constitution. They also create a cultural divide that influences how we live, what we wear and even what we eat and drink. Individuals usually identify with one tribe or the other, but sometimes they need some elements of the enemy's identity - David Cameron seeks a dash of the down-to-earth Roundhead, while Ed Miliband looks for some Cavalier charisma. Featuring contributions from Laurence Llewelyn-Bowen, AS Byatt, Julian Fellowes, Philippa Gregory, Anne Widdecombe and Clarissa Dickson Wright. Are you a Roundhead or a Cavalier?