The Black Pope: A History of the Jesuits (1896)

Margaret Anna Cusack (1829 –1899), who wrote under her religious name "Mary Francis Cusack" was first an Irish Anglican nun, then a Roman Catholic nun, and then a Religious Sister, and the founder of the Sisters of St. Joseph of Peace. By 1870 more than 200,000 copies of her works which ranged from biographies of saints to pamphlets on social issues had circulated throughout the world.

Motivated by the sudden death of her fiancé, she joined a convent of Puseyite Anglican nuns. However, disappointed at not been sent to the Crimean War she converted to Roman Catholicism and joined the Order of St. Clare (also known as the Poor Clares), a community of Franciscan nuns.

She left the Kenmare Poor Clares in November 1881. After leaving the convent, she began to establish shelters and vocational schools for female emigrants to the US and supported herself through lectures and writings.

In 1884, during a personal interview with Pope Leo XIII to seek his support, Cusack obtained permission to leave the Poor Clares and found a new congregation, the Sisters of St. Joseph of Peace.

In 1888 she returned to the Anglican Communion after an altercation with her bishop and issued "The Nun of Kenmare: An Autobiography" the following year. Afterwards she wrote and lectured as tirelessly as ever, writing: "The Black Pope: History of the Jesuits" (1892).