Short answers, pulled from the story.
Norse mythology was little known outside Scandinavia until the 19th century. Antiquaries such as George Webbe Dasent brought the mythology to popular notice in Germany and England during that period, after which it spread into European literary culture and eventually into global entertainment.
Wagner borrowed characters and themes from Norse mythology to compose the four operas that make up Der Ring des Nibelungen, also known as The Ring of the Nibelung. He also drew on medieval German sources and Germanized the names of the Norse gods in the process.
Tolkien stated that his fantasy works The Hobbit (1937), The Lord of the Rings (1955), and The Silmarillion (1977) were heavily influenced by the myths of the Northern Europeans. Through the popularity of those books, Norse-derived conceptions of elves, dwarfs, and trolls became standard elements of the fantasy genre.
Thor has been one of the longest-running superheroes in the Marvel Universe, with a starring role in The Avengers comics and the Marvel Cinematic Universe. Loki, depicted as Thor's adopted brother, serves as one of the franchise's main antagonists. Additional Norse figures in the Marvel Universe include Odin, Freyja, Brunnhilde/Valkyrie, Heimdall, Hela, Balder, Sif, and Fenrir.
The 2018 video game God of War is loosely based on Norse mythology, with Baldr as the main antagonist and Freya, Mímir, and Jörmungandr as allies. Kratos' son Atreus carries the original name Loki in the story. The 2022 sequel God of War Ragnarök depicts events inspired by the Ragnarok narrative and features Týr, the Norns, Thor, and Odin as major characters.
The Viking metal genre centers on Viking Age and Norse mythology, with Bathory, Falkenbach, Turisas, Ensiferum, Finntroll, Týr, Doomsword, and Amon Amarth among its practitioners. Manowar has released Norse-themed material across albums from 1983 through 2011, including the 2007 concept album Gods of War. Norwegian project Wardruna focuses specifically on music inspired by the Futhark runes.