I fail to infer the exact point of historical introduction of STL into actual C++ standard library from the wikipedia article: https://en.wikipedia.org/wiki/Standard_Template_Library
It appears to me that C++11 was somehow significant for this STL, as it was becoming a part of C++ Standard Library. But I find another publication much earlier in 2000 itself: http://dl.acm.org/citation.cfm?id=557814