The Cavaleiro is shown to be a failed military man. In the dialogue between Avisa and the Cavaleiro frequent mentions are made by both parties about an unsucessful and costly siege .Avisa remarks that the Cavaleiro has failed to scale walls and the Caveliero makes a comment that " it kills a martial manly heart then depart before the town has yielded" . I believe the passage is directly referring to the failed seige of the walled city of Rouen in france. This seige was lead in 1591 by Robert Devereux and was a complete debarcle . Due to unnecessary bravado Robert Devereux's only brother Walter was killed. The siege was very costly in terms of both human life and financial resources. Robert Devereux proved himself to be a reckless and headstrong leader who would not follow orders. in 1592 he was ordered back to England and faced severe criticism from both Elizabeth and the Cecil faction.