君士坦丁十一世
Loukas Notaras (; 5 April 1402 – 3 June 1453) was a Byzantine statesman who served as the last "megas doux" or grand Duke (commander-in-chief of the Byzantine navy) and the last "mesazon" (chief minister) of the Byzantine Empire, under emperors John VIII Palaiologos and Constantine XI Palaiologos.