Complex sentence: In 1891 Odhner opened a branch of his factory in Germany, unfortunately, he had to sell it in 1892 to "Grimme, Natalis & Co." because of the difficulty of having two manufacturing facilities so far apart.
Split into simpler sentences: In 1891 Odhner opened a branch of his factory in Germany. Unfortunately, he had to sell it in 1892 to "Grimme, Natalis & Co." because of the difficulty of having two manufacturing facilities so far apart.