It's spring 1153 at Momsbury Abbey in Wiltshire, England.

20-year-old Henry Plantagenet bangs his fist against the Abbey entrance and demands entry.

The large wooden door opens a crack to

reveal the pale face of a monk who pleads with Henry to guarantee the safety of the people

inside. Soldiers rustle impatiently behind Henry stepping closer to the monk. Twelve years ago,

England was plunged into a civil war, which will come to be known as the anarchy.

Henry's mother, Matilda, claims she was the rightful monarch and that the throne had been usurped by Henry's uncle Stephen.

Now Henry's here with an army to seize Momsbury, but the townsmen are loyal to King Stephen, and they've taken refuge in the abbey.

Henry ignores the monks please, and pushes the door open, standing back as his soldiers charge into the abbey with swords drawn. Henry draws his own

sword and follows them into the abbey, but the men of Momsbury are unarmed and offer no threat.

The two groups eye each other warily, until the tension is broken by one of Henry's soldiers,

who steps forward and plunges his sword into the chest of a nearby townsman.

The killing begins a mass slaughter, as Henry's soldiers attack the townsfolk.

Even the monks who enter the fray and beg for mercy are killed.

The last surviving men of Momsbury tried to make a desperate

rush for the exit, but it's of no use. Every last one of them are cut down by Henry's soldiers,

and blood covers the Abbey floor. The massacre at Momsbury Abbey breaks a long-held convention

in medieval warfare,

that the consecrated ground of a church should not be the location of violence.

The brutality of Henry's troops will horrify England's clergy,

but it will not prevent Henry ascending to the throne as the country's next king.

And as king, Henry will once again become embroiled in a killing on church

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