Why did southerners seek territorial expansion

The issue of the expansion of slavery reared its head even as the Panic of 1819 put a damper on postwar nationalism and patriotism. By 1820 Missouri had a population of about sixty thousand, including ten thousand slaves, making it the first territory within the Louisiana Purchase with enough people to become a state. Before that could happen, Congress had to pass an enabling act to allow Missouri to create a state constitution and then must approve the resulting document.

new england colonies endured bitterly cold winters and mild summers

the colonists made their living fishing, whaling, and shipbuilding. the fish included cod, mackerel, herring, halibut, hake, bass and sturgeon.