The Norse explored the Gulf of Saint Lawrence in the 11th century .
The Norse were followed by fifteenth and early sixteenth century European mariners , such as John Cabot , the brothers Gaspar , Miguel Corte - Real , and Alonso Sanchez .
The Norse explored the Gulf of Saint Lawrence in the 11th century and were followed by fifteenth and early sixteenth century European mariners , such as John Cabot , the brothers Gaspar , Miguel Corte - Real , and Alonso Sanchez .