"I think the most important document that we have is one that explains why there are Mennonites in Manitoba & Western Canada and why there are Mennonites in Mexico"
In past centuries, there were barriers or allowances to what you could do based on what group you were part of. It was a time of group rights or collective rights. Mennonites in the 16th and 1700s living in present day Poland, for example, negotiated their rights with local authorities for their village for their business and for their churches. These rights allow them to exist, set taxation levels, or allow them to produce and sell certain products. These documents outlining group rights or privileges were known as Privilegium. It was how the world that they lived in worked.
When Mennonites moved to Russia, the terms of the move were laid out in a document based on collective rights. Today, we don't talk about group rights, but individual rights. (See below for a copy of the actual document)
Host & Archivist Conrad Stoesz covers the rest of the story on "the most important document in the Mennonite Heritage Archives" throughout Episode 2 of "Still Speaking" season three, and you can listen to it in its entirety, below: