The given name Selwyn has its origins in the Welsh language and culture, dating back to the Middle Ages. It is believed to be a compound name derived from the Welsh words "Sel," meaning "sight" or "vision," and "gwyn," meaning "white" or "fair." Together, the name Selwyn can be interpreted as "white sight" or "fair vision."

During the medieval period, the name Selwyn was primarily found in Wales and the surrounding regions influenced by Welsh culture. Its earliest recorded use can be traced back to the 13th century, when it appeared in historical records and manuscripts from that era.

While there are no definitive accounts of the name's appearance in ancient texts or religious scriptures, it is believed to have been a common name among the Welsh nobility and gentry during the Middle Ages and the Renaissance period.

One of the earliest recorded individuals with the name Selwyn was Selwyn ap Rhys (born around 1220), a Welsh landowner and nobleman who played a prominent role in the conflicts between the Welsh princes and the English monarchy during the 13th century.

In the 16th century, Selwyn Gwyn (1510-1588) was a notable Welsh scholar and writer who made significant contributions to the preservation and promotion of the Welsh language and literature.

Another prominent figure with the name Selwyn was Selwyn Lloyd (1904-1978), a British politician who served as Foreign Secretary and Chancellor of the Exchequer in the 1950s and 1960s.

In the field of literature, Selwyn Jepson (1899-1976) was a renowned British novelist and short story writer known for his works exploring the lives of ordinary people in rural England.

Selwyn College, one of the constituent colleges of the University of Cambridge, was founded in 1882 and named after George Augustus Selwyn (1809-1878), the first Bishop of New Zealand and a prominent figure in the Anglican Church.

Throughout history, the name Selwyn has been borne by individuals from various walks of life, including nobility, scholars, writers, politicians, and religious figures, reflecting its enduring presence and significance within Welsh culture and beyond.