Complex sentence: When they arrived in what is now LaPorte County, there was nothing but virgin forest and wild prairie, the New England settlers cleared roads, built farms, constructed churches, erected government buildings, and established post routes.
Split into simpler sentences: When they arrived in what is now LaPorte County, there was nothing but virgin forest and prairie. The New England settlers cleared roads and brush, developed farms, constructed churches, erected government buildings, and established post routes.