Eufranio Desideri was the third of eight children born to John Desideri, a wool merchant, and Serafina Paolini. His parents died when the boy was 12 years old, and he was raised and educated by his uncle Battista Desideri, a teacher in Viterbo, Italy. Desideri arranged a marriage for Eufranio with a local noble family, but the young man felt a call to religious life. Worry over his vocation and fear of hurting his uncle made Eufranio sick; he returned to Leonessa, Italy to recover. There he met and was greatly impressed by a group of Capuchin monks. When Eufranio told his uncle of his desire to join them, Desideri insisted that he continue his studies.
Eufranio agreed, and moved to Spoleto, Italy to do so, but kept in contact with the monks. Following a novitiate year in which the monks did everything to test and dissuade the young man, he joined the Capuchin Franciscans on 8 January 1573 at age 18, taking the religious name Joseph. He suffered through several self-imposed austerities including fasting three days a week and sleeping on bare boards. He was ordained at Amelia, Italy on 24 September 1580. He preached throughout the regions of Umbria, Lazio and Abruzzi regions of Italy. Father Joseph once converted an entire band of 50 highway bandits, who then showed up as a group for his Lent sermons.
He became a missionary to Muslim Pera near Constantinople (modern Istanbul, Turkey), receiving his commision on 1 August 1587. He was also a chaplain for 4,000 Christian galley slaves. He often offered to take the place of some slave who was being worked to death, but the authorities never accepted. Ministering to prisoners in a remote camp, he once got home late, and was forced to sleep outside the walls of his assigned area; he was charged with being a spy for being in the wrong place, and spent a month in jail. He preached to any who would listen, brought lapsed Christians back to the Church and converted Muslims. He also worked with prisoners during a plague outbreak.
Joseph repeatedly sought an audience with the Sultan; he planned to ask for a decree of religious freedom. His forceful methods led to his being arrested and condemned to death for trespassing on royal property. Hung by hooks over a smoky fire for three days, he was freed (legend says by an angel), and returned to Italy, in autumn 1589.
There he resumed his vocation of wandering preacher to small villages throughout the country, preaching to and for the poor, and spread the teachings of the Council of Trent. He helped establish hospitals, homeless shelters, and food banks. He ministered in prisons, to the sick, and the poor. With his crucifix in hand, he would wade into gang fights and brawls, praying, and preaching peace and good sense.
He died on Saturday 4 February 1612 at Umbria, Italy of cancer and post-operative problems from surgery for that cancer. His feast is February 4.