Kenneth MacAlpin (Medieval Gaelic: Cináed mac Ailpin, Modern Scottish Gaelic: Coinneach mac Ailpein; 810 – 13 February 858) or Kenneth I was King of Dál Riada (841–850), King of the Picts (843–858), and the first King of Alba (843–858) of likely Gaelic origin. He inherited the throne of Dál Riada from his father Alpín mac Echdach, founder of the Alpínid dynasty. Kenneth I conquered the kingdom of the Picts in 843–850 and began a campaign to seize all of Scotland and assimilate the Picts, for which he was posthumously nicknamed An Ferbasach ("The Conqueror"). Forteviot became the capital of his kingdom, and he also fought the Britons of the Kingdom of Strathclyde and the invading Vikings from Scandinavia. Kenneth also relocated relics including the Stone of Scone from an abandoned abbey on Iona to his new domain.

Kenneth I is traditionally considered the founder of Scotland, which was then known as Alba, although like his immediate successors, he bore the title of King of the Picts. One chronicle calls Kenneth the first Scottish lawgiver but there is no information about the laws he passed.