Robert Guérin du Rocher was born in Repas in 1736. He was the younger brother of Petrus and like his brother became a Jesuit priest.
He did missionary work in the Middle east and eventually settled as a pastor in Salonika, before being expelled by the Ottomans. On returning to France he bacmae spiritual director for the Sisters of the Visitation in Paris.
On the 2nd September 1792 he was one of the priests, along with his older brother Petrus killed by a mob in the September Massacres. 134 years later he and his fellow Holy September Martyrs were beatified by Pope Pius XI in October 1926