Saint Samson of Dol (born late 5th century) was a Christian religious figure who is counted among the seven founder saints of Brittany. Born in southern Wales, he died in Dol-de-Bretagne, a small town in north Brittany.

Life
Samson was of noble blood, the son of Amon of Dyfed and Anna of Gwent. His father's brother also married his mother's sister, and their son Saint Magloire was his cousin. As part of the prophecy concerning his birth, his parents placed him under the care of Saint Illtud, abbot of Llantwit to become a monk. Later, after the death of Saint Pyr, Samson became abbot of Llantwit's daughter house on Caldey Island. He was ordained bishop by Bishop Dubricius on the Feast of the Chair of Saint Peter (February 22) at the beginning of Lent, which can be calculated to have fallen in the year 521, the only certain date in Samson's life. If the usual practice was observed and he was 35 years old at the time of his ordination, this would mean he was born in 486. However, he is recorded as having been in attendance at a church Council in Paris held at some time between 556 and 573. Had he been born in 486, he would have been at least 70 years old at the time.

Following his ordination, Samson travelled to Cornwall, the Channel Islands, and Brittany. In Cornwall, he founded a monastery that was located at either South Hill or Golant, and, in Brittany, he founded the monastery of Dol. Samson also participated in Breton politics, successfully petitioning the Merovingian king, Childebert I, on behalf of King Judwal. He was buried, with his cousin Magloire, in the Cathedral of Dol. He is one of the seven founder saints of Brittany, with Saint Pol Aurelian, Saint Tugdual (Tudwal), Saint Brieuc, Saint Malo, Saint Patern, and Saint Corentin.

Records
The primary source for his biography is the Vita Sancti Samsonis, written sometime between 610 and 820, but clearly based on earlier materials. Not only does it preserve such details about Samson such as his abstinence from alcohol – unlike many of his contemporaries, such as the Abbot Pyr who was killed when he fell down a well while drunk – but valuable details about Celtic Christianity in Britain during Samson's time. This document details the contacts churchmen in Britain had with both Ireland and Brittany, describes their belief, and offers facts that have been used to prove both that religious communities were headed by abbots where the bishops served in a subordinate role, and that these communities were actually headed by bishops as was the usual practice in the rest of Europe. This Vita was later used as a model for the writing of other hagiographies in Brittany.