Joseph was born an illegitimate child in 1792. His father, a soldier in the Emperor’s army, couldn’t marry Joseph’s mother through being called away. His mother earned a living mending clothes. Joseph grew up with his mother in poverty in Salzburg.
His godfather ( a clergyman) had Joseph entered into grammar school and then into a seminary. Alongside these studies he spent much time studying music and partly financed this by performing as a musician.
In time he was ordained and Oberndorf was his third place of ministry. Soon after the event of Christmas 1818, however, Joseph Mohr, at his own request, moved on to another parish, still as a curate. He doesn't seem to have got on well with the pastors of the parishes as he was transferred eleven times between 1819 and 1827.
In 1828 he became a pastor in Hintersee, where he stayed till 1837 when he moved to Wagrain to be the pastor there. It's there that he became well-known as a person with a strong social conscience, who stood up for the poorest and who refused to accept the existing social order.

He died of pneumonia in poverty in 1848. His grave in the graveyard of the church in Wagrain is honoured to this day.