Green’s Dictionary of Slang

(US) a derog. term for a Portuguese person.

1873		A.S. Evans A la Calif. 44: These men are all ‘Gees’—Portuguese—from the Azores or Western Islands.
1912		R.C. Murphy Logbook for Grace (1948) 7 July 7: The Old Man [...] vows that the iron hoops [...] encourage drowsiness among the ‘mokes’ and the ‘gueez’ (Portuguese).