c.1545-1613. Roman Catholic archpriest. Educated at Trinity College, Oxford, where he was made a fellow in 1566, he was attracted to the Roman Catholic Church and entered the English College at Douai in 1574. Ordained in 1575, he was sent back to England in the following year as one of the first missionary priests. After the death of William Cardinal Allen in 1594, he was appointed archpriest in 1598 to provide leadership for the English Roman Catholics. As a friend of the Jesuits in England he lost the support of some of the secular clergy. For a number of years there were serious divisions about the attitude of Roman Catholics to the English crown. In 1606 James I imposed an oath of loyalty, and Blackwell after a period of imprisonment took the oath despite papal opposition. In 1608 he was deprived of his office as archpriest. He died a supporter of Catholic loyalty to the Crown.