In the Name of the Grandfather/References

Cultural References
The dialogue for the German Krusty the Clown Show has a veiled Nazi reference within.

Krusty: "Heil, heil" Mel: "Ach, Du lieber! Krusty spritzen der Gaswasser." Krusty: "Ja, ja - Krusty spritzen der Gaswasser."

Krusty's "Heil Heil" was a reference to the mandatory greeting in Nazi Germany, "Heil Hitler" ("Heil" literally means "hail" as in greetings to).

Mel's lament "Krusty spritzen der Gaswasser" is grammatically incorrect. The noun Gaswasser (The German normally say "mineralwasser" and it means seltzer water or club soda) is a neuter noun which takes the article "das." Also, the verb form is not correct. A closer rendition would be "Krusty spritzt das Gaswasser."

The sequence further parodies the rarely-seen Monty Pythons Fliegende Zirkus, a purpose-built and specially filmed German-language version of Monty Python's Flying Circuscreated by the Pythons for showing in Germany.

The episode takes its title from a traditional Christian benediction: "In the name of the Father, the Son and the Holy Spirit."

Marge, Bart and Lisa parody the classic video game "Q-Bert" as they chase up and down the Giant's Causeway.

Kathy Ireland is shown during a short sequence. As revealed in the subtitles in the shot, the producers had invited her to appear and voice the cameo, but she declined.

Grandpa mentions about feeling "as lonely as Estes Kefauver at a meeting of Murder, Incorporated." When the Simpsons look at him blankly, he retorts, "That actually means something! Look it up!" Senator Estes Kefauver headed highly-publicized hearings into organized crime in the 1950s. The hearings were a serious blow to the Mob in America, though they are more remembered these days for a side hearing on juvenile deliquency that became a referendum on comic books and the direct cause for the creation of the Comics Code Authority.

Mac's Fifth Avenue is a parody of Saks Fifth Avenue.

Sham-Rock Cafe is a parody of Hard-Rock Cafe.

Hewlett Fitzpackard is a parody of Hewlett-Packard.

Mick-rosoft is a parody of Microsoft.

Cisc O'systems is a parody of Cisco Systems

The Judge in Homer and Grandpa's trial looks similar to Mr. Potatohead

It is not clearly defined where Dunkilderry lies. Although the episode should play in main Ireland, the policemen's uniforms and vehicles at the raid are rather northern Irish (British). The vehicle doors are marked with "POLICE", although in the republic of Ireland, Police is generally and officially called "Garda Siochana" (gaelic for: "Guardians of the peace of Ireland"), and policemen are called "Guardai". Still, only one scene later, in the court, Chief Wiggum is seen accidently knocking down the Irish flag, although one of the policemen, who participated in the raid earlier (and therefore is northern Irish), guards the Irish court.