Complex sentence: Toward the end of the war, Madison Parish faced problems with jayhawkers sympathetic to the Union, who according to historian Winters, were holed up in the impenetrable cane and cypress swamps in the area.
Split into simpler sentences: Toward the end of the war, Madison Parish faced problems with jayhawkers sympathetic to the Union. According to historian Winters, they were holed up in the impenetrable cane and cypress swamps in the area.