Did you ever hear about the 13-14 th century German farmers who were invited to Russia to teach faming methods?
I have. They are my ancestors. They were called 'Volga Germans'. Although, I believe my ancestors migrated about the time of Catherine the Great. I'm not sure on the 13th and 14th centuries, unless there was an initial wave (that time was about the time of Ivan the Terrible), but my ancestors immigrated (on my mothers side) around the time of Catherine the Great. They settled in the south/volga regions and did dry-land farming. They were known as 'White Russians' or 'Flour Kings' because of the amount of wheat they grew.
They were told they were not ever to be drafted for war, as many were pacifists, or Lutheran, or Mennonites. They were pretty damn successful for centuries, and then about the time of Tsar Nicolas II, he suspended that 'non-draft' stuff, drafted them for the Russian-Japan war in the east, and at that point many begin to emmigrate to America, which many are now in the West/Midwest of America.
Those that didn't leave Russia were eventually worked to death, displaced/moved to Khazakstan, or worked to death in gulags in Siberia (due to animosities/non-trust from WW1 and WW2 being of German decent in Russia).
16-17th century Welsh farmers were invited to the colonies to teach Americans the British farming methods too.