World of Darkness is a series of tabletop role-playing games, originally created by Mark Rein-Hagen for White Wolf Publishing. It began as an annual line of five games in 1991–1995, with Vampire: The Masquerade, Werewolf: The Apocalypse, Mage: The Ascension, Wraith: The Oblivion, and Changeling: The Dreaming, along with off-shoots based on these. The series ended in 2004, and the reboot Chronicles of Darkness was launched the same year with a new line of games. In 2011, the original series was brought back, and the two have since been published concurrently.

Mark Rein-Hagen, stylized as Mark Rein•Hagen, is an American role-playing, card, video and board game designer best known as the creator of Vampire: The Masquerade and its associated World of Darkness games. Along with Jonathan Tweet, he is also one of the original two designers of Ars Magica.