Clyst St Mary is located in Devon

Clyst St Mary was the site of one of the decisive battles in the 1549 Prayer Book Rebellion, when West Country resistance to the Protestant Reformation was quashed. After the Battle of Woodbury Common on 4 August 1549, the rebels under the control of Humphrey Arundell had re-grouped with the main contingent of 6,000 at Clyst St Mary, but on 5 August were attacked by a central force led by Sir William Francis, under the control of John Russell, 1st Earl of Bedford. After a ferocious battle Russell's troops gained the advantage leaving a thousand Cornish and Devonians dead and many more taken prisoner, 900 of whom were massacred later that day at Clyst Heath. The village was burned and many of the combatants and villagers drowned in the river.^[3][4]

• http://en.wikipedia.org/wiki/Clyst St Mary