 Complete the following phrase:  Giovanni Giustiniani Longo , Iōánnēs Lóngos Ioustiniánēs; ; 1418  1 June 1453 was a Genoese captain, a member of one of the greatest families of the Republic of Genoa, a kinsman to the powerful house of Doria in Genoa, and protostrator of the Eastern Roman Byzantine Empire. He led 700 professional soldiers, both Genoese and Greeks from the island of Chios, which at the time was part of the Republic of Genoa, to the 