Ninian was the first British missionary to devote himself to work among the pagan Picts of southern Scotland.  In Scotland, Ninian was also called Ringan, and was known as Trynnian in Northern England. The exact dates of Ninian’s life are not known for certain. Bede is our main source of information about him. According to Bede, Ninian was born in southern Scotland and received instruction in Christianity in Rome. He was ordained bishop probably in 394. The most significant influence on Ninian, however, was Martin of Tours, whose monastic life and evangelical zeal Ninian admired, and after whom he named the church he built at Whithorn, in Galloway, south-west Scotland. Ninian became the first of a succession of British missionaries, including Patrick, Columba, Aidan, Willibrord, and Boniface.

Ninian’s diocese covered a large area of southern Scotland. He also established a monastery at Whithorn, thus introducing monasticism to Scotland at an early date. The name “Whithorn” (white house - candida casa), stems from the fact that Ninian built in stone, which was unusual among the Britons. Other sources suggest that Martin sent masons from the continent to help Ninian build the church. Whithorn became a base for missionary journeys around southern Scotland, north of the Roman wall. The monastery at Whithorn later became an important centre of learning for the church in Wales and Ireland. Ninian died about 432 and was buried at Whithorn.