"Wilhelmus van Nassouwe", usually known just as "Wilhelmus", is the national anthem of both the Netherlands and its sovereign state, the Kingdom of the Netherlands. It dates back to at least 1572, making it the oldest national anthem in use today, provided that the latter is defined as consisting of both a melody and lyrics. Although "Wilhelmus" was not recognized as the official national anthem until 1932, it has always been popular with parts of the Dutch population and resurfaced on several occasions in the course of Dutch history before gaining its present status. It was also the anthem of the Netherlands Antilles from 1954 to 1964.

A national anthem is a patriotic musical composition symbolizing and evoking eulogies of the history and traditions of a country or nation. The majority of national anthems are marches or hymns in style. American, Central Asian, and European nations tend towards more ornate and operatic pieces, while those in the Middle East, Oceania, Africa, and the Caribbean use a more simplistic fanfare. Some countries that are devolved into multiple constituent states have their own official musical compositions for them ; their constituencies' songs are sometimes referred to as national anthems even though they are not sovereign states.