It was released as a standalone app in 2006 (after having a labs beta period prior) as Google Talk, and integrated into Gmail in 2007. While the widget in Gmail (which was only removed very recently to replace it with a Meet widget!) was labelled Chats, the service itself never was.
> chat integrated into Gmail before it was branded Google Talk.
Hangouts chat came wayyyy after Google Talk or even its integration into gmail (I know, it's hard to keep track of the chronology of these Google services, they release 2 new ones a year)
