George Leo Haydock was born on 11 April 1774 in Cottam, Preston, Lancashire, the heart of Catholic resistance to the Penal Laws that the English government used to enforce Anglicanism. His parents were George Haydock and his second wife, Anne (née Cottam), who produced a generation that would become outstanding in Catholic service. Their eldest son, James Haydock (1765–1809), became a priest who died caring for the sick of his congregation during an epidemic; the next, Thomas Haydock (1772–1859), became a prominent publisher of Catholic books. Among three daughters, Margaret Haydock (1767? – 1854), joined the Augustinian nuns, taking the name Sister Stanislaus. George was the youngest son. He and his father were namesakes of an illustrious ancestor, Blessed George Haydock (1556–1584), a martyred "seminary priest" during the Elizabethan persecution, beatified in 1987. While attending a school established for Catholic students at Mowbreck Hall, Wesham, George received Confirmation, taking the name Leo, after the fifth-century saint, Pope Leo I, whose liturgical feast was at that time celebrated on Haydock's birthday (see General Roman Calendar as in 1954). In 1785, at eleven years of age, he was sent to further his education at the English College, Douai, (English spelling, "Douay" or "Doway" ) France, established in the 16th century for Catholic exiles, where provision was made for secondary education in addition to training for the priesthood. Among his classmates were many who would go on to play significant roles in the English church, including future bishop Thomas Penswick; the future historian John Lingard; and the future Irish Liberator Daniel O’Connell.