Giovanni Giustiniani

Giovanni Giustiniani Longo (Greek: Ιωάννης Λόγγος Ιουστινιάνης, romanized: Iōánnēs Lóngos Ioustiniánēs; Latin: Iovianus Iustinianus Longus; 1418 – 1 June 1453) was a Genoese nobleman, mercenary captain, and defender of Constantinople during its siege in 1453. He was instrumental in its defense and commanded 700 men, as well as leading the land forces protecting the city.

Source: Wikipedia — https://en.wikipedia.org/wiki/Giovanni_Giustiniani