Complex sentence: The South had resisted policies such as tariffs to promote industry and homestead laws to promote farming because slavery would not benefit; with the South gone, and Northern Democrats very weak in Congress, the Republicans enacted their legislation.
Split into simpler sentences: The South had resisted policies such as tariffs to promote industry and homestead laws to promote farming because slavery would not benefit. With the South gone, and Northern Democrats very weak in Congress, the Republicans enacted their legislation.