1595-1600 - dates between which he was born. 1633 - produced his most important work, 'The herball … gathered by John Gerarde … very much enlarged and amended by Thomas Johnson, citizen and apothecarye of London'. 1643 - joined the forces of King Charles I, took part in the defence of Basing House, Old Basing, Hampshire. 1644 - Johnson shot, contracted a fever, and died a fortnight later, presumably at or near Basing House.