Konstantinos Graitzas Palaiologos, commander of the imperial garrison at Salmenikon near Patras during the invasion of the Despotate of Morea by the forces of the Ottoman Empire in 1460, descends from an obscure branch of the Palaiologos family, but has shown far more valor than his distant relatives, the siblings and co-ruling Despotes Thomas Palaiologos and Demetrios Palaiologos.

Whereas the former had fled to Modon, Corfu, and finally Constantinople, and the latter had surrendered outright to the Sultan, Graitzas has maintained his position.

He holds his redoubt until July 1461, long after the surrender of his lords, at which point he is offered safe passage and a commission in the armed forces of the Republic of Venice.