Revolutionary songs are political songs that advocate or praise revolutions. They are used to boost morale, as well as for political propaganda or agitation. Amongst the most well-known revolutionary songs are "La Marseillaise" and "The Internationale". Many protest songs can be considered revolutionary - or later become canonized as revolutionary songs following a successful revolution. On the other hand, once a revolution is established, some of the aspects of protest song may be considered counter-revolutionary.