Cleon is of Greek origin, derived from the word 'kleos', which means 'glory'. It was popular among ancient Greeks and has been used as a given name throughout history. Cleon gained prominence in ancient Athens during the Classical period, with notable figures such as Cleon the Athenian, a prominent politician and orator of the fifth century BCE. The name has also been associated with figures from other cultures, including Cleon II of Pontus, a king who ruled in the second century BCE. Today, Cleon is still used as a given name but is considered quite rare.
It appears that the name Cleon was quite popular among parents during the early to mid-20th century, with a notable spike in its usage between 1917 and 1925. However, it seems to have fallen out of favor by the late 1930s and early 1940s, as there were only five births each in 1935, 1936, 1937, and 1942 with this name. Overall, a total of 189 children named Cleon were born over the span of these years.