Larry,
All the German states were independent duchys or kingdom. They never could
agree on a common language. There was always high Dutch and low Dutch. It is
said, that even the famous Grimms brothers could not agree on one national
language.
Beyond that... various countries like Mecklenburg, Poland, and Russia offered
free land to anyone willing to clear it and farm it. Mecklenburgers realized
that they could not defend themselves from the invaders from the east and
formed an alliance with the Germans. As these people moved in they were
better equiped with metal farm tools and the land prospered from their crops.
Later on they were mistreated by the countries that invited them to live
there in the first place.
I wish I could remember where I read the details. But I understand even when
some of the Germans formed an alliance (Prussia) Mecklenburg did not join
them immediately. Usually alliances were formed for the purpose of
protection from invaders. Unlike the United States these alliances were not
always permanent. But think of it as the United States of Germany. German
speaking people who formed a common government with a ruler not elected
officials. Today the German states we call Germany are not all of the
original states. Everything East of the Oder River is now in Poland and
Austria which at one time was considered part of Germany is a separate
country.
The end result, they never could agree to disagree and remain united. Wars
and different rulers were the cause as well. I'm sure that the people living
in Mecklenburg today can tell you the exact time of their alliance but you
also need to ask what was the reason behind it all.
Best Wishes,
Dolly