He is known for his critiques of the work of other members of the College of Arms, most particularly in A Discoverie of Certaine Errours Published in Print in the Much Commended 'Britannia' 1594, which touched off a feud with its author, the revered antiquarian and herald William Camden.
[3] Such bitter infighting among the heralds was common; Sir William Segar (Garter 1606–1633) also objected that Cooke made numberless grants to "base and unworthy persons for his private gaine onely.
"[3][5] In December 1616 Brooke tricked Segar into confirming foreign royal arms to Gregory Brandon, a common hangman of London who was masquerading as a gentleman.
[6] Brooke's Catalogue and Succession of the Kings, Princes, Dukes, Marquesses, Earles and Viscounts of this Realme of England since the Norman Conquest was published in 1619.
[7] Brooke died on 16 October 1625 and was buried inside St Mary's Church, Reculver, where he was commemorated by a black marble tablet on the south wall of the chancel, showing him dressed in his herald's tabard.