Muggles' Guide to Harry Potter/Characters/Augustus Rookwood

Overview
Augustus Rookwood was an Unspeakable, working in the Department of Mysteries in the Ministry of Magic.

Note that in early editions of the British version of Harry Potter and the Order of the Phoenix, the name appears as Algernon Rookwood. It is corrected in later editions.

Goblet of Fire
In Albus Dumbledore's Pensieve, Harry re-lives Dumbledore's memory of a hearing at the Wizengamot, in which Igor Karkaroff is naming Death Eaters in an attempt to get his sentence reduced. The only name he comes up with that is unknown to the Aurors is that of Augustus Rookwood, who had been passing information to the Death Eaters. Rookwood is apparently an employee of the Ministry.

Immediately after this, Harry relives Dumbledore's memory of the trial of Ludovic Bagman. Bagman says that he had been passing information to Rookwood, but that he thought he was "one of ours," as he was in the Ministry. In part, perhaps, because of his fame (he was still a Beater for the Wimbourne Wasps Quidditch team at that point), he is absolved of all charges and released.

Order of the Phoenix
Augustus Rookwood is one of the ten Death Eaters who break out of Azkaban. We later learn that they have broken out because the Dementors have left to join Voldemort.

In one of Harry's dreams where he is sharing Voldemort's thoughts, he sees Rookwood reporting to Voldemort that the plan that had been suggested for retrieving something from the Ministry was bound to fail. Rookwood had worked in the Department of Mysteries, and knew about the protective measures in place.

Rookwood is one of the twelve Death Eaters who take part on the Battle at the Ministry. He is the only Death Eater not assigned a partner during the chase. He is later seen during the final battle dueling Kingsley Shacklebolt.

Deathly Hallows
Rookwood takes part in the battle at Hogwarts at the end of this book. Percy Weasley sees him, and takes off after him. He is last witnessed by Harry fighting and losing to Aberforth Dumbledore.

Strengths
The only time we directly see him, Rookwood is carrying bad news to Voldemort, and quite evidently in fear of punishment for carrying that news. We can assume that he has some strength of character, as many Death Eaters learn that Voldemort is in the habit of retaliating against the messenger; it must take some spiritual strength to inform Voldemort that his plan is doomed to failure.

Weaknesses
It could be argued that his loss dueling an elderly wizard (Aberforth Dumbledore) indicates a lack of magical ability. Against this, of course, we must mention that Aberforth was a member of an extremely powerful Wizarding family who was not only running a somewhat shady pub without apparent assistance from bouncers, but had been known for his dueling ability when he was at Hogwarts.

Relationships with Other Characters
Apart from one brief scene, where we see him cringing before Voldemort in fear for punishment for bringing bad news, we have no direct experience with Rookwood. However, we can guess that he is persuasive, as he had convinced people to pass information to him before he was imprisoned. Judging by everyone's reaction when Karkaroff named him as a Death Eater and Ludo Bagman's claims that his father was a friend of Rookwood's, he was probably affable and well-liked during his time as a spy.