The name Renly is believed to have originated from the Old English name Renli or Reinli, which itself is derived from the Germanic root words "ragin" meaning "counsel" and "lind" meaning "tender" or "soft." Its earliest recorded use dates back to the 7th century in the Anglo-Saxon regions of what is now England.

One of the earliest written records of the name Renly can be found in the Domesday Book of 1086, a detailed survey of land and property ownership commissioned by William the Conqueror. The name appears as "Renlius" in this historical document, referring to a landowner in the county of Wiltshire.

In the 12th century, a Renly is mentioned as a knight and retainer of King Henry II in the chronicles of the time. This particular Renly is noted for his participation in the Third Crusade, which took place between 1189 and 1192.

During the 13th century, a Renly de Clifford is recorded as being a member of the landed gentry in the county of Herefordshire. He is mentioned in several legal documents and charters from that period, indicating the name's continued use among the nobility.

In the late 15th century, a Sir Renly Boleyn is recorded as being a courtier and diplomat in the service of King Henry VII. He is believed to have been an ancestor of the famous Anne Boleyn, who later became the second wife of King Henry VIII.

Another notable individual with the name Renly was Renly Wilkins, a 17th-century English clergyman and author. He was born in 1616 and is best known for his work "A Discourse Concerning the Gift of Prayer," published in 1673.

While the name Renly has seen sporadic use throughout history, it has remained relatively uncommon compared to other English given names. Its rarity and unique sound have contributed to its enduring appeal for some parents seeking a distinctive name with historical roots.