Ninian is a Christian saint, first mentioned in the 8th century as being an early missionary among the Pictish peoples of what is now Scotland. For this reason he is known as the Apostle to the Southern Picts, and there are numerous dedications to him in those parts of Scotland with a Pictish heritage, throughout the Scottish Lowlands, and in parts of Northern England with a Northumbrian heritage. He is also known as Ringan in Scotland, and as Trynnian in Northern England.

The Picts were a group of peoples in what is now Scotland north of the Firth of Forth, in the Early Middle Ages. Where they lived and details of their culture can be gleaned from early medieval texts and Pictish stones. The name Picti appears in written records as an exonym from the late third century AD. They are assumed to have been descendants of the Caledonii and other northern Iron Age tribes. Their territory is referred to as "Pictland" by modern historians. Initially made up of several chiefdoms, it came to be dominated by the Pictish kingdom of Fortriu from the seventh century. During this Verturian hegemony, Picti was adopted as an endonym. This lasted around 160 years until the Pictish kingdom merged with that of Dál Riata to form the Kingdom of Alba, ruled by the House of Alpin. The concept of "Pictish kingship" continued for a few decades until it was abandoned during the reign of Caustantín mac Áeda.