Assassin's Creed is a historical action-adventure video game series and media franchise published by Ubisoft and developed mainly by its studio Ubisoft Montreal using the game engine Anvil and its more advanced derivatives. Created by Patrice Désilets, Jade Raymond, and Corey May, the Assassin's Creed video game series depicts a fictional millennia-old struggle between the Order of Assassins, who fight for peace and free will, and the Knights Templar, who desire peace through order and control. The series features historical fiction, science fiction, and fictional characters intertwined with real-world historical events and historical figures. In most games, players control a historical Assassin while also playing as an Assassin Initiate or someone caught in the Assassin–Templar conflict in the present-day framing story. Considered a spiritual successor to the Prince of Persia series, Assassin's Creed took inspiration from the novel Alamut by the Slovenian writer Vladimir Bartol, based on the historical Hashashin sect of medieval Iran (Persia).

The first Assassin's Creed game was released in 2007, and the series has featured fourteen main installments in total, the most recent being Assassin's Creed Shadows in 2025. Main games in the Assassin's Creed series are set in an open world and played from the third-person view. Gameplay revolves around combat, stealth, and exploration, including the use of parkour to navigate the environment. The games feature both main and side missions, and some titles also include competitive and cooperative multiplayer game modes.

A new story and occasionally new time periods are introduced in each entry, with the gameplay elements also evolving. There are three overarching story arcs in the series. The first five main games follow Desmond Miles, a descendant of several important Assassins throughout history, who uses a machine called the Animus to relive his ancestors' memories and find powerful artifacts called Pieces of Eden in an attempt to prevent a catastrophic event, referencing the 2012 phenomenon. From Assassin's Creed IV: Black Flag to Assassin's Creed Syndicate, Assassin initiates and employees of Abstergo Industries (a company used as a front by the modern-day Templars) record genetic memories using the Helix software, helping the Templars and Assassins find new Pieces of Eden in the modern world. The next three games, Assassin's Creed Origins, Odyssey, and Valhalla, follow ex-Abstergo employee Layla Hassan on her own quest to save humanity from another disaster.

The main games in the Assassin's Creed franchise have received generally positive reviews for their ambition in visuals, game design, and narratives, with criticism for the yearly release cycle and frequent bugs, as well as the prioritising of role-playing mechanics in later titles. The series has received multiple awards and nominations, including multiple Game of the Year awards. It is commercially successful, selling over 250 million copies , becoming Ubisoft's best-selling franchise and one of the best-selling video game franchises of all time. While main titles are produced for major consoles and desktop platforms, multiple spin-off games have been released for consoles, mobiles, and handheld platforms. A series of art books, encyclopedias, comics, and novels have also been published. A live-action film adaptation of the series was released in 2016.

Development history While the games in the series have had several narrative arcs, Ubisoft views the series as currently having three periods of development and design philosophy. Until 2015's Assassin's Creed Syndicate, the franchise was structured around single-player content, and while centering on open world spaces and incorporating several role-playing elements, the games were more action-adventure and stealth-oriented. Period two, covering from Assassin's Creed Origins to Assassin's Creed Mirage, brought in more role-playing elements and live-service features to increase player engagement. Period three launched with Assassin's Creed Shadows, using lessons from the second period of development to make engrossing single-player games similar to the original titles, but with features to allow players to share achievements and content with others through a new Animus Hub system.

Period one The first Assassin's Creed game originated out of ideas for a sequel for Ubisoft's video game Prince of Persia: The Sands of Time, aiming for the seventh generation of video game consoles. The Ubisoft Montreal team decided to take the gameplay from The Sands of Time into an open-world approach, taking advantage of the improved processing power to render larger spaces and crowds. Narratively, the team wanted to move away from the Prince being someone next in line for the throne and instead have him work for it. Combined with research into secret societies, they ultimately chose to focus on the Order of Assassins, based upon the historical Hashashin sect of Ismaili, who were followers of Shia Islam. In developing the narrative, the team took heavy inspiration from the 1938 novel Alamut, which focuses on the Assassins under Hassan-i Sabbah during the Crusades. They initially developed a story where the player would control an Assassin escorting a non-playable Prince, leading them to call this game Prince of Persia: Assassin, or Prince of Persia: Assassins. Ubisoft was apprehensive to a Prince of Persia game without the Prince as the playable character, but this led the marketing division to suggest the name Assassin's Creed, playing off the creed of the Assassins in Alamut: "nothing is true; everything is permitted". Ubisoft Montreal ran with this in creating a new intellectual property, eliminating the Prince, and basing it around the Assassins and the Knights Templar in the Holy Land during the 12th century. Additionally, in postulating what other assassinations they could account for throughout history, they came onto the idea of genetic memory and created the Animus device and modern storyline elements. This further allowed them to explain certain facets of gameplay, such as accounting for when the player character is killed, similar to The Sands of Time.

After Assassin's Creed was released in 2007, the Ubisoft Montreal team felt that they needed to "rework the global structure" in developing the sequel, Assassin's Creed II. They believed parkour was underutilized in the first game and designed the world in the sequel to feature freerun highways to make it easier to enter into parkour moves; for example, using rooftops to escape pursuits. The change in setting meant that the game would feature a new cast of characters, including a new protagonist, Ezio Auditore da Firenze. Assassin's Creed II also brought in more use of crowds to hide in plain sight that the developers had seen used in Hitman: Blood Money, adding to the concept of social stealth as a gameplay option. Finally, Ubisoft Montreal completely reworked the repetitive mission structure from the first game through numerous side activities, collectibles, and secrets. These additions became a central part of the series going forward, as well as of other Ubisoft games like Watch Dogs, Far Cry, and Tom Clancy's Ghost Recon. Assassin's Creed II was followed by two direct sequels, Assassin's Creed: Brotherhood and Assassin's Creed: Revelations, which also featured Ezio as the main protagonist and introduced the ability for players to recruit NPCs as Assassins and manage them in missions.

Assassin's Creed III originated from both Ubisoft Montreal, who wanted to progress the series' narrative forward in time, and an unattached project that had been developed at Ubisoft Singapore and featured naval ship combat. As the main team had settled on the American Revolution period for the game, they found the ship-to-ship combat system fit with the story and redesigned the setting to incorporate it further. Another major change in Assassin's Creed III was transitioning the parkour and freerun systems to work in the natural woodlands of 18th-century Massachusetts and New York. This further allowed the addition of trees and other vegetation within the city areas themselves, not just as part of the parkour systems, but to add more varied environments, which would continue as part of the series' ongoing design.

For Assassin's Creed IIIs sequel, Assassin's Creed IV: Black Flag, the Ubisoft team built upon the foundation of its predecessor, particularly with regard to the naval gameplay, merging it seamlessly with the land-based gameplay. The team also used the game as a chance to address aspects of the series' storyline unexplored in previous titles. Choosing to focus on an outsider's perspective to the Assassin–Templar conflict, they set the game around the Golden Age of Piracy, with the protagonist, Edward Kenway, starting out as a pirate who initially becomes involved in the conflict with the prospect of wealth. Similarly, after the conclusion of Desmond Miles' story arc in Assassin's Creed III, the modern-day segments put players in the role of a nameless individual controlled from a first-person perspective. The team chose this approach because they believed it allowed players to more easily identify themselves in their character. This trend would continue in the series until Assassin's Creed Syndicate.

Development of Assassin's Creed Unity began shortly after the completion of Brotherhood in 2010, with the core development team splitting off during the early stages of development on Assassin's Creed III. As the first game in the series to be released exclusively for the eighth generation of video game consoles, Unity featured a graphical and gameplay overhaul. The setting chosen for the game was Paris during the early years of the French Revolution, with players taking control of a new Assassin named Arno Dorian. After Unity, Ubisoft released Assassin's Creed Syndicate in 2015.

Period two Following Syndicates release, Ubisoft decided that the series needed a major reinvention across both gameplay and narrative. It was decided to make the next game, Assassin's Creed Origins, closer to a role-playing video game than a stealth-action game, which would also bring a game with many more hours of play than previous titles. Some long-standing features of the series were eliminated for this purpose, such as the social stealth mechanic. This changed how missions were presented—rather than being linearly directed through the Animus, the player character could meet various quest givers in the game's world to receive missions. From the narrative side, Ubisoft placed the game before the formation of the Assassin Brotherhood in Ancient Egypt and made the player character, Bayek of Siwa, a medjay that people would respect and seek the help of. The modern-day storyline also shifted back to a single character, Layla Hassan. The developers limited the number of playable sequences for her character compared to previous games but gave them more meaning, such as allowing the player to explore Layla's laptop with background information on the games' universe.