Recap / The Simpsons S 20 E 21 Coming To Homerica

The Norwegian-born citizens of Ogdenville migrate to Springfield after their tainted barley crop (which was put into Krusty Burger's latest sandwich) causes an economic collapse.

Tropes:

http://tvtropes.org/pmwiki/pmwiki.php/Recap/TheSimpsonsS20E21ComingToHomerica