There is a clear distinction between a framework and library. AFAIK a library is focused to solve a particular problem for instance routing, data validation, i18n, state management, view rendering (like templates systems), data models etc... On the other hand framework try to tackle a set of related problems into a coherent/logical workflow. For instance there is not a single library that can handle by itself the issue of isomorphic apps. Angular is a framework, reactjs is a library but http://reactboilerplate.com/ is framework using reactjs.
I think backbone is framework not a library it tackles several issues (class system, views, and middle end) and it does it badly but that's a topic of ~another post~ the past.
Historically Javascript community has favoured the do-it-yourself framework hence or because there is a lot of libraries you can choose from or because the needs of everyone are so different that's it's difficult to create a miningful framework. Mind the fact that Google previous "framework" named Google closure was a stdlib kind of framework compared to the competition of MV* framework like emberjs or angular it did not force a given workflow.
I think backbone is framework not a library it tackles several issues (class system, views, and middle end) and it does it badly but that's a topic of ~another post~ the past.
Historically Javascript community has favoured the do-it-yourself framework hence or because there is a lot of libraries you can choose from or because the needs of everyone are so different that's it's difficult to create a miningful framework. Mind the fact that Google previous "framework" named Google closure was a stdlib kind of framework compared to the competition of MV* framework like emberjs or angular it did not force a given workflow.