Llewelyn is an ancient Welsh masculine given name derived from the Old Welsh elements 'llyw' meaning 'leader' and 'elwyn' translating to 'flowing, smooth'. It has been historically associated with notable figures such as Llewelyn ap Iorwerth, also known as Llewelyn the Great, a medieval prince of Gwynedd who ruled in the 12th century. The name gained popularity during the Welsh language revival movement in the late 19th to early 20th centuries and has since been chosen by parents seeking unique yet historically significant names for their sons.
"The name Llewelyn experienced notable peaks in popularity during the past two decades, with a combined total of 49 births in 2021 and 2022 alone. Prior to this, there was a significant gap in usage between 1978 and 2015, suggesting a revival or renewed interest in the name."