Complex sentence: In 1778, Catherine the Great invited Armenian merchants from the Crimea to Russia and they established a settlement on the Don, which they named "Nor Nakhichevan", after one of the ancient areas of Armenia, Nakhichevan.
Split into simpler sentences: In 1778, Catherine the Great invited Armenian merchants from the Crimea to Russia. After moving to the area, they established a settlement on the Don, which they named "Nor Nakhichevan", after one of the ancient areas of Armenia, Nakhichevan.