title: Walter Devereux, 1st Earl of Essex
context: Walter Devereux was the eldest son of Sir Richard Devereux, who was created a Knight of the Bath on 20 February 1547 and died that same year, in the lifetime of his father, The 1st Viscount Hereford. [1] Walter Devereux's mother was Lady Dorothy Hastings, daughter of The 1st Earl of Huntingdon and Anne Stafford, said to have been a mistress of Henry VIII. Through his paternal ancestry he was related to the Bourchier family, to which previous Earls of Essex had belonged:[2][lower-alpha 1] John Devereux, son of Walter Devereux who died at the Battle of Bosworth, married Cecily Bourchier, sister of Henry Bourchier, 2nd Earl of Essex.[1]
question: When was Walter Devereux made a knight?
answers: 20 February 1547