In 865AD a great Viking army invaded Britain. The violence that followed engulfed half the country and altered the course of British history. At the head of the army was a mysterious, fearsome warlord called Ivarr, known to history by his nickname, 'Ivarr the Boneless'. Little is known about Ivarr from historical sources but in the Danish Sagas, larger than life tales written down centuries later, he emerges from the shadows of the Dark Ages in full colour: a great military strategist; a ruthless invader driven by revenge. But an intriguing detail about Ivarr has sparked a remarkable historical quest. The Sagas describe Ivarr's traumatic birth and claim that he had 'only the like of gristle where bones should have been'. They also say he needed staves on which to be carried into battle. Could Ivarr's nickname 'boneless' hint at something exceptional? Nabil Shaban, a writer and performer who suffers from a condition called Brittle Bones Disease, believes that Ivarr may have suffered the same disability. This programme recounts the story of the most brutal invasion Britain has ever suffered and follows Nabil's quest to explore the possibility that Ivarr, the leader of the invasion, was physically disabled. (C4 Press) In 2003 Nabil Shaban, a disability rights advocate with osteogenesis imperfecta, made the documentary 'The Strangest Viking' for Channel 4's Secret History, in which he explored the possibility that Ivarr 'the Boneless' may have had the same condition as himself. It also demonstrated that someone with the condition was quite capable of using a longbow, and so could have taken part in battle, as Viking society would have expected a leader to do.