In karaoke bars from Lima to Beijing, at street festivals from San Antonio to Madrid, and in the heart of La Habana, one song can be heard: Guantanamera. Perhaps no other song illustrates the Cuban identity as much as this one, which has been covered by artists all over the world. Because of its popularity, its author is often noted as “Canción Popular” — as in, it doesn’t have an author — but that isn’t the case. One Joseíto Fernández was the creator of the singular tune, and Cuba celebrated his 100th birthday yesterday.

The city of La Habana is commemorating Joseíto’s life all this week with roundtables, singing contests and other events, even a serenade of the song at the late artist’s residence, joined by his now elderly children.

Aside from the international appeal the song has enjoyed, perhaps the most fascinating thing about the Guantanamera phenomenon is its mutation, which continues today. Venezuela’s El Universal reports that the song was written in its original form by Joseíto, but through its constant performance has benefitted from improvisation in the lyrics, with artists adapting the words to suit a certain situation, ranging from political strife to personal problems. The most popular version, the one we hear the most today, includes the words of Cuban hero José Martí, intregated into the music — ironically — by American folk singer Pete Seeger.

Guantanamera the song was composed when Joseíto was just 20, and itself turns 80 years old this year.

Via / El Universal