Warhammer Fantasy (later renamed Warhammer: The Old World) is a fictional fantasy universe created by Games Workshop and used in many of its games, including the table top wargame Warhammer, the Warhammer Fantasy Roleplay (WFRP) pen-and-paper role-playing game, and a number of video games: the MMORPG Warhammer Online: Age of Reckoning, the strategy games Total War: Warhammer, Total War: Warhammer II and Total War: Warhammer III and the two first-person shooter games in the Warhammer Vermintide series, Warhammer: End Times – Vermintide and Warhammer: Vermintide 2, among many others.

Warhammer is notable for its “dark and gritty” background world, which references a range of historical cultures such as the Holy Roman Empire, Mesoamerica, ancient Egypt, and medieval France, and is populated with a variety of races such as humans, high elves, dark elves, wood elves, dwarfs, undead, orcs, lizardmen, and other creatures familiar to many fantasy/role-playing settings.

The development of the setting began with the release of a game simply called “Warhammer” in 1983. The setting is followed by a soft reboot known as Warhammer Age of Sigmar, created in 2015.

The Warhammer world drew inspiration from Tolkien’s Middle-earth, but also from Robert E. Howard (Conan the Barbarian) and Michael Moorcock, as well as real-world history, particularly European history. What is recognisable as the Warhammer World began with the expansion material to the first edition of the game Warhammer, but was formulated as a distinct setting with a world map in the second edition.^{[citation needed]}

The Warhammer World borrowed considerably from historical events and other fantasy fiction settings. The Old World is recognisably Europe approximating to various historical periods including the Renaissance—the Empire being set over what was the Holy Roman Empire—medieval France, Roman Italy and Celtic Britain. Many events are lifted and modified directly from history, including the Black Plague and the Moorish invasion of Spain, and others from original fantasy sources. Like Middle-earth, Warhammer's Dwarfs are declining in population, the Elves have mostly departed for homelands in the West, and a Great Necromancer is reborn after the defeats in his Southern stronghold.^{[citation needed]}

The world of Warhammer Fantasy has some of the largest distribution of races and cultures in pop fantasy.

The world most prominent, often proves to be the most susceptible to the corrupting influence of Chaos. Most of the featured human nations are based in the Old World (analogous to real Europe): The Empire (Holy Roman Empire), Bretonnia (France and Arthurian Britain), and Kislev (Slavs of Russia, Poland, and Ukraine). Further east of them is another powerful human civilisation known as Grand Cathay (corresponding to China). There is also Nippon (Japan), and Araby (based loosely on the various Middle Eastern powers that ruled throughout the Middle Ages and Renaissance, most notably the Ottoman Empire).

Many factions, such as the Elves, the Lizardmen, the Ogres and the Halflings, have been created by the Old Ones: star-travelling gods responsible for the creation of most of the setting's sentient races. These Old Ones were brought low by the daemonic forces inadvertently unleashed by the collapse of their Warp Gates (one on the North Pole and one on the South Pole), leaving their creations to fend for themselves. This backstory also provides an easy explanation for the presence of a variety of familiar fantasy races. Ogres and Halflings, for example, are closely related. Both are resistant to the mutating effects of Chaos energies (fuelled by hearty appetites and efficient metabolisms), but have opposite physical templates.^{[citation needed]}