In this essay, start with the acquisition of Florida. Look at the Missouri Compromise and the issue of the expansion of slavery and the balance between free and slave states. How did Indian Removal open the western areas to cotton farming? How does the territory the US takes from Mexico after the MX-AM War affect the issue of slavery? You should cover the Wilmot Proviso and the Free Soil Party. How does the California Gold Rush affect this issue? You should look at the compromise of 1850. How does the Kansas- Nebraska crisis fit in? What are the results? (Bleeding Kansas, Charles Sumner etc).