1530s, "of or relating to cities or towns," from Middle French urbain (14c.) and directly from Latin urbanus "belonging to a city," also "citified, elegant" (see urban). The meaning "having the manners of townspeople, courteous, refined" is from 1620s, from a secondary sense in classical Latin. Urbanity in this sense is recorded from 1530s. For sense connection and differentiation of form, compare human/humane; german/germane.
Urbane; literally city-like, expresses a sort of politeness which is not only sincere and kind, but peculiarly suave and agreeable. [Century Dictionary]