Go with God and Fight Like the Devil.

A fascinating hero and the pursuit of a sword with mythical power - this is the remarkable new novel by Britain's master storyteller, which culminates at the Battle of Poitiers in 1356. The Hundred Years War rages on and the bloodiest battles are yet to be fought. Across France, towns are closing their gates, the crops are burning and the country stands alert to danger. The English army, victorious at the Battle of Crecy and led by the Black Prince, is invading again and the French are hunting them down.
Thomas of Hookton, an English archer known as Le Batard, is under orders to seek out the lost sword of St Peter, a weapon said to grant certain victory to whoever possesses her.

As the outnumbered English army becomes trapped near the town of Poitiers, Thomas, his men and his sworn enemies meet in an extraordinary confrontation that ignites one of the greatest battles of all time.