Review: This episode ended the 20th season well. Could they have aired it on the Norwegian national holiday, Syttende Mai, on purpose? The turning point for Marge and the family was when Maggie spoke with a Norwegian accent, suggesting that the cultural impact of immigration is more important than the economic impact. The ambiguous ending was typical. As a Norwegian-American, I found the cultural references funny enough to give the episode an A.
DYN... ... Lisa has an en-suite bathroom? ... Homer emerging from the chimney to serve lemonade? ... Nelson holds up a sign that says "Haw Haw"? (And we've been spelling it "ha ha" in here for 20 seasons.) ... the school bus arriving at the wall build with school employees? ... Homer and Marge now agree that he is an alcoholic? (First time?)
References
Sideshow Bob coming into the Cheers bar is obviously a reference to Kelsey Grammer, who voices Sideshow Bob and also was a regular on Cheers.
"Beef-fed barley" is a reference to "grain-fed beef," which many restaurants, especially in Canada, claim they serve.
Builder's Barn is a reference to The Home Depot, many of whose locations are known for illegal aliens/migrant workers/day laborers seeking work in the parking lot.
Misc.
In the part of the opening paying homage to "The Brady Bunch," the family disappears into the door at the top of the stairway. This is known as the "mystery room" in Brady fandom, because it was never seen being used for anything. Its door opens inward, so it probably isn't a closet.
This episode was the first time Lisa has vomited. She was spared by her vegetarianism from an earlier round of food poisoning that affected the meat-eating Simpsons.
There are more bathrooms in the house than we've seen before. If Lisa has an en-suite one, there must be three upstairs, because Marge and Homer have an en-suite bathroom that's been seen previously.
The town being founded by Norwegians 100 years ago is odd. 1909 was well after the peak of the Norwegian immigration around 1870. If the Norwegian immigrants had come then, you would think the descendants would be well assimilated by now. Only a few senior citizens still speak with Norwegian accents in the heavily Norwegian town where I was raised. You rarely hear anyone under 70 say "ja."
The episode incorporates a lot of Norwegian bits. Characters are named Inga, Torbjorn, and Magnus. The phrases "ja" and "uff da" are used. "Uff da" means roughly "that's awful." Lingonberry is a popular fruit and flavoring in Norway and among Norwegian-Americans. The Minnesota Vikings was of course named for the legendary Norse seamen and raiders. (About the time the Minnesota Vikings was founded, the controversy over whether the Kensington Runestone found in central Minnesota proved that Vikings had visited Minnesota was hot. Most authorities believe it is fake although politicians still pay lip service to the idea that it is genuine.) Aquavit (akavit) is a Norwegian liquor. It is of comparable proof to vodka, so it would definitely not be consumed like beer, as Homer did. The Norwegian flag and even a Norwegian coin are shown.
Norway is famous for its intricately patterned and very expensive sweaters. They can be found at specialty shops in areas with a large Norwegian-American population (and of course via Internet). Few American owners of these sweaters wear them for everyday use, instead getting them out for special occasions. (On the day this episode aired, I traveled to the Syttende Mai parade in Brooklyn with a group of Norwegian-Americans, many of whom were wearing Norwegian sweaters.)
The Norwegians are obviously used as a proxy for Mexicans in this immigration-themed episode. Of course, the controversy in the U.S. is about international immigration and not the migration of people from one town to another. Many aspects of Mexican immigration are parodied in this episode, such as the Minutemen, the border fence, authorities being lackadaisical toward border enforcement, and phrases like "doing jobs we don't want to do ourselves."
Where Is Springfield?
Milhouse comments that Springfield is in Tennessee Titans country. According to the sports project at CommonCensus.org, the fan base of the Titans is heavily concentrated in Tennessee and small parts of adjacent states.