Henry Garnet, sometimes Henry Garnett, was an English Jesuit priest executed for high treason, based solely on having had advanced knowledge of the 1605 Gunpowder Plot and having refused to violate the Seal of the Confessional by notifying the authorities. Born in Heanor, Derbyshire, he was educated in Nottingham and later at Winchester College before he moved to London in 1571 to work for a publisher. There he professed an interest in legal studies and in 1575, he travelled to the continent and joined the Society of Jesus. He was ordained in Rome some time around 1582.

Oswald Tesimond, SJ was an English Jesuit born in either Northumberland or York who, while not a direct conspirator, had some knowledge of the Gunpowder Plot beforehand.