In December 1884, Pope Leo XIII granted independence to St. Mary’s Priory. On February 11, 1885, James Zilliox was elected as the first abbot of Newark by monks of the Eastern Province—an unusual election not involving the local community due to the absence of monks with stability in Newark. Thirteen monks, including Zilliox, transferred their vows to establish the abbey.
Fr. James Zilliox, OSBJames Zilliox, a native of Newark and son of early parishioners, had trained under Wimmer and studied in Rome, Germany, and Austria. A scholar and contemplative by temperament, he had participated in reformist efforts within St. Vincent and was initially removed from leadership due to internal conflicts. Yet, Wimmer trusted him and returned him to positions of authority, culminating in his election as abbot.

Zilliox sought to instill contemplative rigor and Beuronese liturgical aesthetics in Newark. He restructured monastic assignments, sold off the Denville farm, and acquired theological resources. However, his vision met resistance from a community oriented toward pastoral and educational work. His fragile health and tuberculosis compounded his frustration, leading him to resign in 1886—barely a year after his installation.