Johannes Grant was an engineer employed by the Byzantine Empire at the fall of Constantinople in 1453. Contemporary Greek accounts referred to him as being German, although more recent scholarship has suggested he may actually have been Scottish, named "John Grant". His use of counter-tunnelling prevented the Turks from weakening or invading Constantinople from under the walls.
- ^ Bartusis, Mark, Late Byzantine Army
- ^ Runciman Fall of Constantinople 1453, page 84
- ^ Nicol, Donald, Last Centuries of Byzantium. Cambridge University Press, 1993 [2nd edition]. Chapter 18.
- ^ The Fall of Constantinopla