Abu Umar was the king of Menorca who lived in the castle of Santa Àgueda near Ferreries. King Pere III of Catalonia visited Menorca while traveling to conquer Africa. However, Abu Umar betrayed Pere III by warning Abu Umar's friends in Africa of the impending attack. In retaliation, Pere III's son Alfonso III later sailed with an army to conquer Menorca from Abu Umar. After a battle in which both sides fought bravely with swords and shields, Abu Umar's warriors surrendered. Alfonso III then conquered Ciutadella and became the new king of Menorca.