ROME — Pope Francis has named the first woman to head a major Vatican office, appointing an Italian nun, Sister Simona Brambilla, 59, to become prefect of the department responsible for all the Catholic Church’s religious orders.

The appointment marks a major step in Francis’ aim to give women more leadership roles in governing the church.

While women have been named to No. 2 spots in some Vatican offices, never before has a woman been named prefect of a dicastery or congregation of the Holy See Curia, the central governing organ of the Catholic Church.

The historic nature of Brambilla’s appointment on Monday was confirmed by Vatican Media, which headlined its report “Sister Simona Brambilla is the first woman prefect in the Vatican.”

The office is one of the most important in the Vatican. Known officially as the Dicastery for the Institutes of Consecrated Life and Societies of Apostolic Life, it is responsible for every religious order, from the Jesuits and Franciscans to the Mercy nuns and smaller newer movements.

The appointment means that a woman is now responsible for the women who do much of the church’s work — the world’s 600,000 Catholic nuns — as well as the 129,000 Catholic priests who belong to religious orders.

“It should be a woman. Long ago it should have been, but thank God,” said Thomas Groome, a senior professor of theology and religious education at Boston College who has long called for the ordination of women priests. “It’s a small step along the way but symbolically, it shows an openness and a new horizon or possibility.”