Linguistic variations across the territories associated with each saint have provided evidence that the Ninian preserved in literary tradition originated from this individual.

James Henthorn Todd, in his 1855 publication of the Leabhar Imuinn (The Book of Hymns of the Ancient Church of Ireland), suggested that it was Finnian of Moville,[5] and that view has gained traction among modern scholars.

[6][7] The earliest mention of Ninian of Whithorn is in a short passage of The Ecclesiastical History of the English People by the Northumbrian monk Bede in c. 731.

However, there is no unchallenged historical evidence to support any of their stories, and all sources had political and religious agendas that were served by their accounts of Saint Ninian (discussed below).

Variations of the story add that he had actually met St Martin, that his father was a Christian king, and that he was buried in a stone sarcophagus near the altar of his church.

Bede says that Ninian (whose name he only renders in the ablative case Nynia) was a Briton who had been instructed in Rome; that he made his church of stone, which was unusual among the Britons; that his episcopal see was named after Saint Martin of Tours; that he preached to and converted the southern Picts; that his base was called Ad Candidam Casam, which was in the province of the Bernicians; and that he was buried there, along with many other saints.

[8] Leaving aside the stories regarding miracles, in the Vita Sancti Niniani Aelred includes the following incidental information regarding Saint Ninian: that his father was a Christian king; that he was consecrated a bishop in Rome and that he met Saint Martin in Tours; that Saint Martin sent masons with him on his homeward journey, at his request; that these masons built a church of stone, situated on the shore, and that on learning of Saint Martin's death, Ninian dedicated the church to him; that a certain rich and powerful "King Tuduvallus" was converted by him; that he died after having converted the Picts and returned home, being buried in a stone sarcophagus near the altar of his church; and that he had once travelled with his brother, named "Plebia".

[11][12] James Ussher wrote that Ninian left Candida Casa for Cluayn-coner in Ireland, and eventually died in Ireland; that his mother was a Spanish princess; that his father wished to regain him after having assented to his training for an ecclesiastical state; that a bell comes from heaven to call together his disciples; that a wooden church was raised by him, with beams delivered by stags; and that a harper with no experience at architecture was the builder of the church.

He adds that a smith and his son, named respectively "Terna" and "Wyn", witnessed a miracle by Ninian and that the saint was granted lands to be called "Wytterna".

Others who wrote of Saint Ninian used the accounts of Bede, Aelred, or Ussher, or used derivatives of them in combination with information from various manuscripts.

The anonymously written 8th-century hagiographic Miracula Nynie Episcopi (Miracles of Bishop Ninian) is discounted as a non-historical account, and copies are not widely extant.

[21] Dedications to Saint Ninian are expressions of respect for the good works that are attributed to him, and the authenticity of the stories about him are not relevant to that point.