From TARDIS Index File, the free Doctor Who reference.

Gaspard de Saux-Tavannes was a Marshal of France and a member of the conspiracy to assassinate Admiral Gaspard de Coligny. When the plan failed, he blamed the Abbot of Amboise for it and had him executed. He was later distressed to learn from that Catherine de Medici that innocent Huguenots were also to be killed during the St. Bartholomew's Day Massacre. (DW: The Massacre of St Bartholomew's Eve)