Ludwin (also called "Liutwin") (? - 717) was the Bishop of Rheims from 691 until 717, and the Bishop of Trier from 697 until 717.

Ludwin was a Frankish noble of the Widoner. He did not have the intention to enter the church; he married a noblewoman of the Robertiners and had two sons, Milo and Wido. His uncle, Basinus, was the bishop of Trier.

Legend states that Ludwin when on a hunting trip fell asleep in a forest clearing one day. An eagle came along and bocked the sun from Ludwin while he slept. When Ludwin and his servants awoke they interpreted it as a sign from god. Ludwin built a chapel in the clearing and dedicated it to St Dionysius; the chapel of St Gangolf still stands in Mettlach.

In c. 690 Ludwin established the Abbey of Mettlach. In 691 Ludwin was appointed the Bishop of Rheims, and after his uncle's death in 697 was also appointed the Bishop of Trier. He soon acquired the Bishopric of Laon also, and thus became one of the most important church officials in the Frankish realm.

In 717 Ludwin died in Rheims and was succeeded in both Rheims and Trier by his son Milo. Milo buried his father in Mettlach, and after the reports of miracles at his grave, his church was rebuilt in 990 in an octagonal shape based on the chapel of Charlemagne in Aachen. In 1247 his remains were transferred to a newly built chapel, and in the 15th Century his remains were again moved to a new chapel which connected to the monastery. After the French Revolution the buildings came under control of the Roch family who at their own expense to the new Liutwinis Cathedral in Mettlach.

Preceded by:

Ludwin (Liutwin)

Succeeded by:

Rigobert Bishop of Rheims
691 - 717
Basinus Bishop of Trier
697 - 717