John Brown (ジョン・ブラウン, Jon Buraun) is Queen Victoria's aide and a member of her Private Secretarial Officers; he often explains things on her behalf and works to cheer her up.
John has short, shaggy hair with two noticeable cowlicks that curl upwards and to the right. He wears large sunglasses, no matter the time of day, that completely veil his eyes. He dresses in a long, double-breasted, button-down trench with a medallion attached over the left breast, lace-up knee-high boots, black gloves, and a white belt cinched at the waist; attached to the belt, on his left hip, is his whip.
John is a very straight-faced and impassive individual. At times he dons a Prince Albert puppet, whose personality he assumes when Queen Victoria is feeling particularly sad about her late husband; however, while he impersonates him, his tone is wooden and monotonous, which reflects his distinctive character. He is extremely loyal to the Queen and is especially keen in extolling her virtues—but he does not override her speech or undermine her authority in any way. He occasionally suffers physical abuse at her hands, such as when the horse she was riding on stepped on his head, but he takes this all in silently and never complains.
Furthermore, one of his bizarre quirks is his devotion to his "beloved" horse, which is strong to the point that he had refused to ride it while traveling from England to Germany, and walked alongside it instead.
Indian Butler Arc
At the Curry Fair, when the host was about to present the trophy to both the Harold West Company and the Funtom Corporation, John uses his whip to confiscate the trophy. Queen Victoria follows up on a horse, trampling him in the process. From beneath the horse, John introduces the Queen, explaining who she is and why she is so well-loved, until she decides she would like to speak. Soon after, when Queen Victoria begins to cry for Prince Albert, he whips out a hand puppet of him, and pretends to be him to console her.
Eventually, Queen Victoria grieves for Prince Albert again, and John comforts her with the hand puppet. Subsequently, she realizes that she has spent too much time at the event, and he assists her in climbing onto her horse and watches as she departs. Ciel Phantomhive then points out that he should be leaving with her, and he chases after her. Later, Ciel discovers that John has slipped an envelope from the Queen into his pocket, which has tickets and a note to lead Ciel on a mission to investigate the Noah's Ark Circus.
Luxury Liner Arc
Public School Arc
Emerald Witch Arc
After Charles Grey and Charles Phipps give their analysis of the plant specimens from the Werewolves' Forest to Queen Victoria, who reads their report and panics. John uses his Prince Albert puppet to soothe the Queen. After she calms down, she proceeds to write a letter instructing Ciel Phantomhive to eradicate the werewolves.
When John learns that Ciel is ill, he is troubled, because the Queen has explicitly ordered for the letter to be read immediately. He, then, requests Sebastian to read the letter's contents in Ciel's stead. Subsequently, John announces his leave, and Sebastian warns him to beware of werewolves. John leaves the forest.
Blue Cult Arc
In Buckingham Palace, John stands beside Queen Victoria, while she holds an audience with Sieglinde Sullivan. He supports the Queen, as they move over to a table, where cakes and tea are prepared. When Sieglinde makes a promise to commit herself to helping England advance, the Queen expresses her delight and compliments Ciel for his work—and in doing so, she mentions her late husband Prince Albert. At the reminder of Albert, she sobs, and John impersonates Albert with his Albert puppet, to comfort her. John comments that Ciel has become like his father, and the Queen agrees, saying that he is very reliable.
- (About Queen Victoria) "This queen is the one who crafted the most brilliant time of Great Britain's history. Not only was she the political power behind the idea of expanding the territories of Great Britain, allowing it to become the 'empire where the sun never sets,' she also made her mark in the fields of fashion at balls and other fashionable events; she was the one leading the trends and had immense popularity amongst the people. To this day, she is still deeply in love with the deceased Prince Albert. This is off topic, but it is said that a popular show, 'The Violent Earl,' was based on her highness."
- According to the official Kuroshitsuji character popularity poll, John is the twenty-eighth most popular character in the series, with 23 votes.
- In the first season of the Kuroshitsuji anime, Ash Landers replaces John as Queen Victoria's aide.
- As the real John Brown was Scottish, Yana Toboso wanted to let him wear a kilt, but ultimately decided against it as it was too "daring."