Bertrand du Guesclin, nicknamed "The Eagle of Brittany" or "The Black Dog of Brocéliande", was a Breton knight and an important military commander on the French side during the Hundred Years' War. From 1370 to his death, he was Constable of France for King Charles V. Well known for his Fabian strategy of avoiding major battles where possible, he took part in seven pitched battles and won the five in which he held command.