When did the East German government announce that all East German citizens could visit West Germany

Explain how zollverein, a tariff agreement, to unite the german states.

What did washington mean when he said patriotism leads to unity

Did the spanish settlers and missions have a positive effect on world history? why, what did they do that was positive? why was the treaty of paris (1763) good for the world/world history? did the plymouth colony have a positive effect on world history? why, what did they do that was positive?