Opera tenor was only Jelen's second job, or actually his third job. His main work was with the
administration of the Kingdom of Bohemia, as an archivist; his second job was as a composer; and in the evening, he would sing
at the opera.
The son of a teacher, he had displayed considerable intelligence early on, so his father sent him to a good school in Prague. At
nine years old, he was on his own, working as a singer at a church choir, and taking music lessons and going to school. His
father died when he was 12 years old, but with the help of patrons, he could continue his studies, and complete them in 1824.
The next 20 or so years were divided between the archives, the music desk and the opera stage. He set Czech texts to music (not
so widespread at the time!), and on stage, he premiered many international operas in Czech translation. In 1840, he founded a choral
society that became instrumental in promoting the Czech language (which was clearly secondary to German under the Hapsburg reign),
and thus helped enhance the Czech sense of national identity. In the 1848
revolution, Jelen engaged in political activities, and was elected into the constitutional convention of the Austrian Empire.
In 1849, he was appointed head of the archives of the Ministry of the Interior, and hence moved to Vienna. He died during one
of his regular trips to Prague.