What treaty brought Russia into the first world war?

Question by Justin: What was the treaty that tied Russia to Serbia and brought Russia into the first world war?
What was the treay that tied Russia to Serbia and brought Russia into the first world war? If you know, please provide some proof, i.e.; link to trusted site.

Answers and Views:

Answer by DiGriz
There was no treaty that “tied” Russia to Siberia. Siberia became part of Russia centuries before WWI.