- Noble belonging to the Galician Gres family.
- In 1366 Andrés Sánchez de Gres was accompanying Álvaro Pérez de Castro to Santiago of Compostela to meet Pedro of Castile, but on hearing that the king had killed the Archbishop of Santiago, they returned to their estates and joined the party of Enrique of Trastámara, recently proclaimed King of Castile. [Pedro, ch. 40: 39-43]
Andres Sanches de Gres