Tatwine (sometimes Tatwin, Tatuini, or Tadwinus) was the tenth Archbishop of Canterbury from 731 to 734. Prior to becoming archbishop, he was a monk and abbot of a Benedictine monastery. Besides his ecclesiastical career, Tatwine was a writer, and riddles he composed survive. Another work he composed was on the grammar of the Latin language, which was aimed at advanced students of that language. He was subsequently considered a saint.
Tatwine was a Mercian by birth.His epigraph at Canterbury stated that when he died he was in old age, so perhaps he was born around 670. He became a monk at the monastery at Breedon-on-the-Hill in the present-day County of Leicestershire, and then abbot of that house. Through the influence of King Æthelbald he was appointed as Archbishop of Canterbury in 731 and was consecrated on June 10, 731. He was one of a number of Mercians who were appointed to Canterbury during the 730s and 740s. Apart from his consecration of the Bishops of Lindsey and Selsey in 733, Tatwine's period as archbishop appears to have been uneventful. He reposed in office on July 30, 734, as was later considered a saint.
He is commemorated on July 30.