Argyll (/ɑːrˈɡaɪl/; archaically Argyle; Scottish Gaelic: Earra-Ghàidheal, pronounced [ɛrˠə ˈɣɛː.əl̪ˠ]), sometimes called Argyllshire, is a historic county and registration county of western Scotland. The county ceased to be used for local government purposes in 1975 and most of the area now forms part of the Argyll and Bute council area.
Argyll is of ancient origin, and broadly corresponds to the ancient kingdom of Dál Riata less the parts which were in Ireland. Argyll was also a medieval bishopric with its cathedral at Lismore. In medieval times the area was divided into a number of provincial lordships. One of these, covering only the central part of the later county, was called Argyll. It was initially an earldom, elevated to become a dukedom in 1701 with the creation of the Duke of Argyll. Other lordships in the area included Cowal, Kintyre, Knapdale, and Lorn. From at least the 14th century there was a Sheriff of Argyll, whose jurisdiction was gradually extended; from 1633 the shire covered all these five provinces. Shires gradually eclipsed the old provinces in administrative importance, and also became known as counties. Between 1890 and 1975, Argyll had a county council. The county town was historically Inveraray, but from its creation in 1890 the county council was based at Lochgilphead.