The name Brendon is derived from the Old Irish name Brénaind, which itself comes from the Celtic words "bren" meaning "prince" or "chief" and the suffix "-ind" meaning "man" or "person." The name can be traced back to the 5th century in Ireland and the British Isles.

One of the earliest recorded individuals with this name was Saint Brendan the Navigator, an Irish monk who lived from around 484 to 577 AD. He is famous for his legendary journey across the Atlantic Ocean, which some historians believe may have reached the shores of North America centuries before the Vikings.

Another notable figure was Brendon Gallacher, a 6th-century Welsh king who ruled the kingdom of Ergyng in present-day South Wales. He is mentioned in several medieval Welsh manuscripts and is remembered for his military victories against the Anglo-Saxons.

In the 9th century, Brendon of Clonfert was an Irish priest and monastic founder who established several monasteries in Ireland and Scotland. He is venerated as a saint in the Catholic Church and his feast day is celebrated on November 29th.

During the Middle Ages, the name Brendon gained popularity among the Norman nobility in England and France. One prominent example was Brendon de Harcourt, a Norman knight who fought alongside William the Conqueror at the Battle of Hastings in 1066.

In more recent history, Brendon Fletcher was a Canadian actor and musician who starred in several films and television shows, including "The Revenant" and "Freddy vs. Jason." He was born in 1981 and tragically passed away in 2020 at the age of 39.