Why were southerners angry when Abraham Lincoln was elected for president?

Abraham Lincoln had gradually become convinced that slavery was morally and ethically wrong, and that it had to end. Southerners were certain that as president, Lincoln would take steps to end slavery and free the slaves. Plantation owners, who relied on slave labor, were especially opposed to what Lincoln wanted to do, but even most ordinary southerners agreed that their states should have the right to own slaves.