Julia was one of the prominent Catholic leaders, along with Kyogoku Maria and others women catechist, who strongly resisted the oppressions imposed on Christianity.
Her father died when her brother, Naito Joan, was a child and his position as heir to Yagi castle seems to have been unstable.
She was a part of the missionary work centered in Kyoto, interacting with the wives and consorts of many Daimyo, converting Gohime (Ukita Hideie's wife and Hideyoshi's daughter) and others to Christianity.
When the Siege of Osaka broke out at the beginning of 1614 at the start of the general persecution of Christianity by the bakufu, Julia and eight other nuns were apprehended, tied up in sacks and carried around the city, then left on the ground for a while.
At the end of the year, they were sent out of the country as dangers to the political order, along with most of the Christian clergy, both Japanese and foreign, and her brother Joan and Takayama Ukon and their families.