Is Tarquin a real name?

[littlepetit]

I always hear ‘tarquin’ as a bit of a joke ‘posh’ name but thinking about it I have NEVER met or encountered a single tarquin or even heard of any friends-of-friends-of-friends called tarquin.

Is it actually a real given name or a myth?

Sheridan from Keeping Up Appearance's 'Friend' who is mother seemed to love that her son had a 'friend' with a posh upper-class name.