Lewis Cass was elected in 1848 defeating incumbent Henry Clay.
Narciso Lopez with other Southern slavers conspires to invade Cuba. Learning of the plot Cass calls on Congress to support them, starting the Spanish-American War in 1851. It ends in 1853 shortly after his reelection. The United States takes Cuba and Puerto Rico from Spain. Cuba would later be admitted as a sate in his third term.
Trade Coup In Japan
Cass sends the navy to "open" Japan up for trade.
Lewis Cass ran against Winfield Scott easily defeating him.
The Kansas-Nebraska Act created the territories of Kansas and Nebraska and authorized them to decide the slavery issue for themselves. This lead to Bleeding Kansas where there was a lot of violent conflict in Kansas between freestaters and slavestaters.
While Lewis Cass experienced serious opposition from within his own party he still managed to secure the nomination. The Whig Party had disbanded and instead he faced Republican John Fremont as his main opponent. He easily defeated him.
Panic of 1857
The country faced another depression. In response Lewis Cass began deficit spending.
A short conflict with Brigham Young and Mormon supporters in the Utah Territory took place. Young would be replaced as territorial governor but he and all other rebels were pardoned by Cass.
Lewis Cass was defeated by Abraham Lincoln in the 1860 election.
Secession Crisis of 1860
Southern states fearing that Abraham Lincoln would abolish slavery began to secede. However, Lewis Cass acted decisively, instructing federal forces to mobilize and to protect federal property in the South. Only South Carolina, Mississippi, and Florida seceded as it became clear to most that any rebellion would be quickly squashed.
Lewis Cass wins a fourth term in 1864. Immediately he begins vetoing northern applications for the creation of new states. He also removes all federal funding from Deseret. Lewis Cass's term is short. He dies in 1866 and is succeeded by his vice president, William Butler