Complex sentence: A prominent and well-known settler in the Iowa Territory, he was one of the earliest settlers in Rock Island and spent much of his life involved in the early settlement of the Mississippi Valley and the "Quad Cities".
Split into simpler sentences: A prominent and well-known settler in the Iowa Territory, he was one of the earliest settlers in Rock Island. He spent much of his life involved in the early settlement of the Mississippi Valley and the "Quad Cities".