During Batman's early years, a stunt man named Hudson Pyle wanted to be a superhero. At first, his reasons were selfish since he wanted to gain fame but began to change into more honorable ones. During his time, he was famous for his sharp swords and quick wits and even his handsome smile. However, his superhero days began to come to an end when he fell in love with a young woman who was being blackmailed by some gangsters. The gangsters learned about her connection to Cavalier and blackmailed him into committing crimes for them. The Cavalier's fame began to deteriorate and driven to the edge, he killed his blackmailers. This led to a fight with Batman and the police where he was gunned down by the police.
Note: This Cavalier appears in Legends of the Dark Knight #32 in the Blades story arc. Cavalier I has been identified as one of the deceased entombed below the Hall of Justice.
The 'New' Knight
Years later, after Batman and Robin had become partners, a new Cavalier surfaced. His name was Mortimer Drake, an antiques collector who couldn't get enough. Drake began to dress as the Cavalier and started to rob museums, collectors, anywhere he could find valuable antiques. Drake later faced Batgirl ( Barbara Gordon) and Batwoman and found himself at a dead end. He couldn't hit a woman and had to resort to a self-examination, then he thought, "the Devil with gallantry" and punched Batgirl in the face. During the Knightfall story arc, he had apparently gone insane for reasons unknown. It's possible his origins have changed since Crisis on Infinite Earths.
One year later
Mortimer Drake is now working for Black Lightning as an informant, it could be that he has now reformed. He is also said to be in a gay relationship with Captain Stingaree. His back is later broken by Bane, and he is reduced to acting as a bodyguard for Leslie Thompkins. His back was broken while battling the Secret Six alongside othervillians. Captain Stingaree was confirmed as a casualty. It is unknown how severe the break was for the Cavalier.
He appears in Secret Six briefly as one of the villains tracking down the Secret Six. During the brawl on the bridge Bane performs a Backbreaker on him probably breaking his back.
For more information see; Batman: The Dark Knight: Knight Terrors
Cavalier is one of many villain injected with a combination of Venom and Fear toxin. The Venom makes him super strong and the toxin makes him fearless. He is taken down by Batwoman, in Devil's Square.
A new Hush in Gotham City is using the motive operadi of former Batman villains. This new Hush tries to murder the Calendar Man with Cavalier's sword but his attempt was interrupted by Terry McGinnis. Terry engages in a brief dialogue with this new Hush and his choice in weapons. Terry reveals that Mortimer Drake, formerly known as the Cavalier, has been dead for quite sometime.
Batman: Brave and the Bold
Mortimer Drake version of Cavalier, appeared in several episodes of "Batman: The Brave and the Bold" tv series, voiced by Greg Ellis. Always speaking in really bad Shakespeare-esqe dialogue(to which Batman remarks "Somewhere Shakespeare is spinning in his grave"). He first appeared in episode "The Eyes of Despero!" tried to rob a bank, but was easily defeated by Batman, with a garbage can lid. He makes another appearance in "A Bat Divided" in shady Gotham City "8 Bar", a known haunt for third-rate costumed villains. Confused by the sudden appearance of three Batmen at first, he quickly decided to attack one of them, only to be tasered by electrified knuckle. He is the only villain in bar, who had a speaking line in this episode.
He next appeared in "Night of the Batmen!" faced off against Green Arrow(who being disguised as Batman) and was rather easily beaten by him. His last speaking appearance was in "Bold Beginnings!", where he allied with Ruby Ryder, to gain full access to her billion dollar trust fund through a false kidnapping. Batman and Green Arrow arrived and agreed to their first team up, to successfully take on the two villains. He also makes cameo appearances in "Night of Huntress" as an inmate at Blackgate Penitentiary, "Mayhem Of The Music Meister" as an inmate at Iron Heights, "Joker: The Vile and the Villainous!" being foiled by Batman from car theft and in series finale "Mitefall", on wrap party for the whole series cast in the Bat Cave.
Mortimer Drake version of Cavalier, briefly appeared in the 1994 BBC radio adaptation of Batman: Knightfall. He was one of the escaped Arkham Asylum inmates, who was quickly defeated by Batman. After the fight, he had a small speaking line: "You broke my nose you cad!".