The Catholic tradition of fasting which began in the 7th century brought about an innovative change in the Western culture. For more than 6 months a year, including Lent and Fridays, people were forbidden from consuming, while fish was an exception. We trace the fish farming techniques and the explosion of demand for fish in the monasteries in the Middle-Ages and address the spread of the fish-eating culture as well as the discovery of the New Continent led by developments in fishing and navigation techniques.