Christian Gaul is a German actor and voice actor born in Berlin in 1964. He completed his acting training at the Mozarteum University in Salzburg, studying from October 1984 to June 1988. Since then, he has built a career encompassing both on-screen acting and extensive voice work for film and television.

Gaul is particularly well-known in Germany for his voice roles in numerous anime series. He frequently provides the German voice for characters originally voiced by Japanese actor Noriaki Sugiyama. His most prominent anime role is William T. Spears, a senior supervisor from the Dispatch Society, in the Black Butler series. He has voiced this character across multiple installments, including Black Butler: His Butler, Performer, Black Butler: Book of the Atlantic, Black Butler II, Black Butler: Book of Circus, and the original Black Butler television series.

Beyond his signature role in Black Butler, Gaul's anime filmography is extensive. He voiced Fresh the Pike in Mardock Scramble: The First Compression. In the series Zombie-Loan, he took on the role of Touhou. He also voiced Dominikov in the OVA series Murder Princess. Other notable anime credits include Xerxes Break in Pandora Hearts, William Farnese in Romeo x Juliet, and roles in various installments of the Detective Conan and City Hunter film series. His work also extends to popular franchises such as Fairy Tail, Beyblade: Metal Fusion, and Kuromukuro.

In addition to his specialization in anime, Christian Gaul is a prolific voice actor for a wide range of live-action and animated productions. He is the official German dubbing voice for actors such as Nick Swardson, John Ross Bowie (whom he voices as Barry Kripke in The Big Bang Theory), and Ethan Suplee. He also provides the German voice for the Muppet character Miss Piggy. His work spans films like Guardians of the Galaxy Vol. 3 and the Sing films, as well as series such as Dexter and Gravity Falls. According to his voice actor profile, he is based in Berlin and is proficient in German and French.