A national anthem is a generally patriotic

Patriotism

Patriotism is a devotion to one's country, excluding differences caused by the dependencies of the term's meaning upon context, geography and philosophy...

 musical composition that evokes and eulogizes the history, traditions and struggles of its people, recognized either by a nation's government

Government

Government refers to the legislators, administrators, and arbitrators in the administrative bureaucracy who control a state at a given time, and to the system of government by which they are organized...

 as the official national song, or by convention

Convention (norm)

A convention is a set of agreed, stipulated or generally accepted standards, norms, social norms or criteria, often taking the form of a custom....

 through use by the people.
Anthems rose to prominence in Europe during the 19th century, but some are much older in origin. The oldest national anthem is the "Wilhelmus

Wilhelmus

Wilhelmus van Nassouwe, usually known just as the Wilhelmus , , is the national anthem of the Netherlands and is the oldest national anthem in the world though the words of the Japanese national anthem date back to the ninth century...

", the Dutch

Netherlands

The Netherlands is a constituent country of the Kingdom of the Netherlands, located mainly in North-West Europe and with several islands in the Caribbean. Mainland Netherlands borders the North Sea to the north and west, Belgium to the south, and Germany to the east, and shares maritime borders...

 national anthem, written between 1568 and 1572 during the Dutch Revolt

Dutch Revolt

The Dutch Revolt or the Revolt of the Netherlands This article adopts 1568 as the starting date of the war, as this was the year of the first battles between armies. However, since there is a long period of Protestant vs...

, which became the official Dutch national anthem in 1932.