Het Wilhelmus (Dutch for The William) is the national anthem of the Netherlands, written in 1574. This makes it the oldest national anthem in the world, though the lyrics of Kimi ga yo date back to the ninth century AD. It was officially adopted in 1932.
The song is about Prince William of Orange, who led a revolt against Spanish rule in the mid-16th century. The song is written in the first person, as from William's point of view. It has 15 stanzas, forming an acrostic, "WILLEM VAN NAZZOV," the subject of the anthem.