The name Elwin has its origins in the Old English language, derived from the elements "elf" and "wine," meaning "elf friend." It dates back to the early medieval period in England, likely emerging around the 7th or 8th century AD. This name was given to children with the belief that it would protect them from harm caused by mischievous elves or fairies.

One of the earliest recorded instances of the name Elwin can be found in the Domesday Book, a comprehensive record of landowners and settlements compiled in 1086 under the orders of William the Conqueror. The name appears in various spellings, such as Ælfwine and Alfwin, reflecting the linguistic evolution of Old English.

In the 12th century, an Elwin of Birkby is mentioned in the Chronicles of Henry of Huntingdon, a medieval historian and author. This Elwin was a landowner and nobleman who lived during the reign of King Stephen of England (1135-1154).

Another notable figure was Elwin, a Benedictine monk from Evesham Abbey in Worcestershire, England, who lived in the late 12th and early 13th centuries. He is remembered for his contributions to the abbey's chronicles and historical records.

During the 13th century, Elwin of Warfield was a prominent English landowner and knight who served under King John and King Henry III. He was involved in various military campaigns and is mentioned in several contemporary chronicles.

In the late 14th century, Elwin Waterton was a cleric and diplomat from Yorkshire, England. He served as the English ambassador to the court of the Holy Roman Emperor and was involved in negotiations related to the Western Schism, a period of rivalry between multiple claimants to the papacy.

While the name Elwin fell out of widespread use in more recent centuries, it has occasionally been revived as a given name, often inspired by its historical and literary associations with the world of elves and fairies.