Complex sentence: The ongoing American Civil War (1861-1865) made life difficult for a young man who was not a soldier, and an African American beside, and in the summer of 1863 he returned to East Saginaw where he began land speculating.
Split into simpler sentences: The ongoing American Civil War (1861-1865) made life difficult for a young African-American man who was not a soldier. In the summer of 1863, he returned to East Saginaw where he began land speculating.