LuÃ s Vaz de CamÃ es ( c. 1524 â `` June 10 , 1580 ) was Portugal 's greatest poet . LuÃ s Vaz de CamÃ es ( ; sometimes rendered in English as Camoens Ë kÃ m oÊ Ë É ns ) ; c. 1524 -- June 10 , 1580 ) is considered Portugal 's , and the Portuguese language 's greatest poet .