Yusuf ibn al-Hasan (c. 1607 – c. 1640), christened Dom Jerónimo Chingulia, was ruler of Mombasa from 1614 to 1632.
The old sultan died around 1609 and was succeeded by his son Hasan, who continued to assert his claim to Pemba, offering the Portuguese 300 bales of rice as a privilege. Relations between the Sultan of Mombasa and the Portuguese deteriorated, particularly between 1611 and 1612. An obnoxious Portuguese captain seized power, demanding more rice sacks from Pemba as payment, and feuds within the Sultan's family caused serious trouble in Mombasa. King Munganaja's uncle (Mwini Nasr) quarreled with Hasan. He went to the captain of Fort Jesús and told him that Hassan was planning a rebellion and was joining forces with his neighboring tribe, the Mussungoro, to overthrow the Portuguese. When questioned, Hasan claimed his innocence, but the Portuguese did not believe him.[1]
They attacked his palace and appointed Munganaja as interim regent. Hasan left Mombasa and settled in Kili, but returned after a faltering ceasefire. Relations between the Portuguese and the Sultan continued to deteriorate until 1614, when a Portuguese ship arrived, and he attempted to bring Hasan to Goa for questioning. When he learned that he was about to be arrested, Hasan fled to his ally Musongoro's fortress (kaya) at Labai on the mainland. However, the African tribesmen succumbed to the Portuguese's bribe of 2,000 pieces of cloth, betrayed and murdered him, and left his body at the Machpa crossing as evidence of the crime. The captain ordered his head cut off and sent to Goa as a miserable trophy.[1][2]
In Goa, news of the assassination was met with dismay. Sultan Hassan had been summoned to Goa to plead guilty, and the murder was not the intended result, Hasan's brother became the ruler of Mombasa instead, and Hasan's son Yusuf, an 11-year-old boy, was taken to Goa to be raised as a Christian. The governor personally acted as the boy's godfather, and his child support was paid out of the state treasury. When the case was finally brought before a Portuguese court in 1618, the Sultan was acquitted of treason. The murdered man's loyalty was wrongfully questioned, and his son was declared the rightful heir to the Mombasa throne. However, the Portuguese governor of Mombasa escaped punishment.[1][2]
Don Jeronimo Chingulia, renamed Yusuf, was educated at the Monastery of Our Lady of Mercy in Goa under the auspices of the Augustinian Order. He was under the viceroy's watch and trained for his role as king. In 1627, in a special ceremony in Goa, he was crowned King of Mombasa, Malindi, and Pemba, and after swearing obedience to the Pope, he was knighted in the Order of Christ. He then traveled to Mombasa and was crowned king.[1][2]
He began to secretly visit his father's grave at night and pray in Islamic fashion. A Portuguese spy sighted him and reported his suspicious behavior to the captain of the fortress. The spy reported what he had seen to the Portuguese captain, but he then returned to the king and warned him that his actions were known. Dom Jeronimo thanked the traitor for warning him and promised him a large reward, but then sent slaves to kill him.[1]
The next day, August 15, 1631, was Ascension Day, an important religious holiday for the Portuguese. The king hurriedly gathered 300 followers and headed to the fort with them as if participating in a festival. The captain, Pedro Leitão de Gamboa, received his guest without suspicion, but when the king drew his sword and stabbed him in the chest, and the king's retainers threw themselves upon the Portuguese, The Portuguese were completely taken by surprise and all killed. Yusuf assumed command of the fortress and city.[1][3]
The King and his followers now turned their attention to the residential areas of Portugal. When they found the Portuguese, they slaughtered them without mercy. Some fled to the Augustinian Monastery, where they endured seven days before running out of food and being forced to surrender. They died too. Over 150 Portuguese men, women, and children were murdered. Only four Augustinian monks and one layman managed to escape the bloodshed and make their way to Pate by boat.[1][4]
In mid-December 1631, a Portuguese fleet of 20 ships and 1,000 men was sent to Mombasa in retaliation. As funds were tight, funding for these ships became a problem, and the usual trade expedition to Ceylon was canceled that year. The ship first called at Pate to gather information and arrived in Mombasa. In January 1632, others from Zanzibar and Muscat joined them to avenge Yusuf's crimes, no doubt enjoying the booty. Yusuf was well prepared, summoning his neighboring tribesmen, the Musungoro, and fortifying their fortresses. His efforts to win the Turks over to his side were unsuccessful, but the Turks sent him a flag, and he hoped that the Turks' presence would be enough to hold off the Portuguese. He raised his banner over the fortress. The Portuguese first attempted to blockade the island by sending boats to nail the fords to Machpa. On 16 January they decided to land troops at Tuaca (Mbaraki in the southwest of the island, then called Nossa Senhora or Tuaca), but heavy seas made the landing impossible.[1][5]
Another landing attempt was repulsed at Kirindini, and more bases were lost to poisoned arrows by Mussungoro archers. On March 11, Portuguese forces landed at a site called the Turkish Fortress, opposite the mainland fortifications. Despite this new foundation, nothing was achieved. As the monsoon was changing, it was finally decided on March 15 to lift the siege, withdraw, and return to Goa.[1][6]
Yusuf then left Mombassa and became a pirate. In 1637 there is one final reference to him at the island of Amissa off Cape Delgado, where he failed to make a surprise raid. He is then supposed to have gone to Shihr in Eastern Yemen to pick up another ship. He died in November 1638 robbed and murdered in the Red Sea by Arab pirates.[1][7]