Battle of Diu

16th-century Mamluks

The Mamluk Sultanate of Egypt was, in the beginning of the 16th century, the main middleman between the spice producing regions of India, and the Venetian buyers in the Mediterranean, mainly in Alexandria, who then sold the spices in Europe at a great profit. Egypt was otherwise mostly an agrarian society with little ties to the sea.[10] Venice broke diplomatic relations with Portugal and started looking for ways to counter its intervention in the Indian Ocean, sending an ambassador to the Mamluk court and suggested that "rapid and secret remedies" be taken against the Portuguese.[11]

The Portuguese in South Asia in the 15th ,16th & 17th centuries.
Light Green - Territories conquered or ceded.
Dark Green - Allies or under influence.
Yellow - Main Factorys

Mamluk soldiers had little expertise in naval warfare, so the Mamluk Sultan, Al-Ashraf Qansuh al-Ghawri requested Venetian support, in exchange for lowering tariffs to facilitate competition with the Portuguese.[11] Venice supplied the Mamluks with Mediterranean-type carracks and war galleys manned by Greek sailors, which Venetian shipwrights helped disassemble in Alexandria and reassemble on the Suez. The galleys could mount cannon fore and aft, but not along the gunwales because the guns would interfere with the rowers. The native ships (dhows), with their sewn wood planks, could carry only very light guns.

Command of the expedition was entrusted to a Kurdish Mamluk, former governor of Jeddah, Amir Hussain Al-Kurdi, Mirocem in Portuguese. The expedition (referred to by the Portuguese the generic term "the rumes"[12]) included not only Egyptian Mamluks, but also a large number of Turkish, Nubian and Ethiopian mercenaries as well as Venetian gunners[10] Hence, most of the coalition's artillery were archers, whom the Portuguese could easily outshoot.

The fleet left Suez in November 1505, 1100 men strong.[10] They were ordered to fortify Jeddah against a possible Portuguese attack and quell rebellions around Suakin and Mecca. They had to spend the monsoon season on the island of Kamaran and landed at Aden at the tip of the Red Sea, where they got involved in costly local politics with the Tahirid Emir, before finally crossing the Indian Ocean.[13] Hence only in September 1507 did they reach Diu, a city at the mouth of the Gulf of Khambhat, in a journey that could have taken as little as a month to complete at full sail.[14]

19th-century map of Chaul

At the time of the arrival of the Portuguese in India, the Gujarati were the main long distance dealers in the Indian Ocean, and an essential intermediary in east–west trade, between Egypt and Malacca, mostly trading cloths and spices. In the 15th century, the Sultan of Gujarat nominated Malik Ayyaz, a former bowman and slave of possible Georgian or Dalmatian origin, as the governor of Diu. A cunning and pragmatic ruler, Malik Ayyaz turned the city into the main port of Gujarat (known to the Portuguese as Cambaia) and one of the main entrepôts between India and the Persian Gulf, avoiding Portuguese hostility by pursuing a policy of appeasement and even alignment – up until Hussain unexpectedly sailed into Diu.[15]

Malik Ayyaz received Hussain well, but besides the Zamorin of Calicut, no other rulers of the Indian subcontinent were forthcoming against the Portuguese, unlike what the Muslim envoys to Egypt had promised. Ayyaz himself realized the Portuguese were a formidable naval force whom he did not wish to antagonize. He could not, however, reject Hussain for fear of retaliation from the powerful Sultan of Gujarat – besides obviously Hussain's own forces now within the city. Caught in a double bind, Ayyaz decided to only cautiously support Hussain.[16]

In March 1508, Hussain's and Ayyaz's fleets sailed south and clashed with Portuguese ships in a three-day naval engagement within the harbour of Chaul. The Portuguese commander was the captain-major of the seas of India, Lourenço de Almeida, tasked with overseeing the loading of allied merchant ships in that city and escort them back to Cochin.[17]

Although the Portuguese were caught off-guard (the distinctively European-like ships of Hussein were at first thought to belong to the expedition of Afonso de Albuquerque, assigned to the Arabian Coast), the battle ended as a Pyrrhic victory for the Muslims, who suffered too many losses to be able to proceed towards the Portuguese headquarters in Cochin.[18] Despite fortuitously sinking the Portuguese flagship, the rest of the Portuguese fleet escaped, while Hussain himself barely survived the encounter because of the unwilling committal of Malik Ayyaz to the battle. Hussain was left with no other choice but to return to Diu with Malik Ayyaz and prepare for a Portuguese retaliation. Hussain reported this battle back to Cairo as a great victory; however, the Mirat Sikandari, a contemporary Persian account of the Kingdom of Gujarat, details this battle as a minor skirmish.[19]

Nevertheless, among the dead was the viceroy's own son, Lourenço, whose body was never recovered, despite the best efforts of Malik Ayyaz to retrieve it for the Portuguese viceroy.

Portuguese nau. With fore and aft castles integrated in the hull and a deeper draught meant to withstand long trans-oceanic voyages, Portuguese carracks were some of the most seaworthy ships of their time.

From Angediva, the Portuguese set sail to Dabul, an important fortified port city belonging to the Sultanate of Bijapur. The captain of the galley São Miguel, Paio de Sousa, decided to investigate the harbour and put to shore, but he was ambushed by a force of about 6,000 men and was killed, along with other Portuguese. Two days later, the viceroy led his heavily armoured forces ashore and crushed the garrison stationed by the riverbank in an amphibious pincer attack. Dabul paid dearly for the act of provocation, as per the viceroy's orders the city was then razed, the surrounding riverside settlements devastated, and almost all their inhabitants killed, along with the cattle and even stray dogs in retaliation.

According to Fernão Lopes de Castanheda, the sack of Dabul gave rise to a 'curse' on the western coast of India, where one might say: "may the wrath of the franks befall you".[24]

Portuguese naval and war banner, featuring the cross of the Order of Christ, which Dom Francisco was part of.

From Dabul, the Portuguese called at Chaul, where Dom Francisco ordered the governor of the town to prepare a tribute to be collected on the return from Diu. Moving towards Mahim, close to Bombay, the Portuguese found the town deserted.[25]

At Bombay, Dom Francisco received a letter from Malikk Ayyaz. Doubtlessly aware of the danger facing his city, he wrote to appease the viceroy, stating that he had the prisoners and how bravely his son had fought, adding a letter from the Portuguese prisoners stating that they were well treated.[26] The viceroy answered Malik Ayyaz (referred to as Meliqueaz in Portuguese) with a respectful but menacing letter, stating his intention of revenge, that they had better join all forces and prepare to fight or he would destroy Diu:

I the Viceroy say to you, honored Meliqueaz captain of Diu, that I go with my knights to this city of yours, to take the people who were welcomed there, who in Chaul fought my people and killed a man who was called my son, and I come with hope in God of Heaven to take revenge on them and on those who assist them, and if I don't find them I will take your city, to pay for everything, and you, for the help you have done at Chaul. This I tell you, so that you are well aware that I go, as I am now on this island of Bombay, as he will tell you the one who carries this letter.[27][28]

In the ten months between the Battle of Chaul and Diu, important developments took place on the Muslim field: Hussain took the chance to careen his ships and recovered a straggled carrack with a reinforcement of 300 men. Notwithstanding, the relationship between Hussain and Ayyaz worsened, with Hussain now plainly aware of the duplicity of Ayyaz, who had taken custody of the Portuguese prisoners at Chaul – which Hussain apparently intended "to send back to Cairo stuffed". Unable to pay the remaining of his troops, Hussain was forced to pawn his own artillery pieces to Ayyaz himself. Presumably, only either the hope of fresh reinforcements or fear of the reaction of the Sultan now prevented him from returning to Egypt.[20]

At this point, should Malik Ayyaz assist Amir Hussain, he risked his city and his life; should he choose to turn on Hussain, the Sultan might take Ayyaz' head. If Hussain stood his ground, he risked annihilation and should he retreat, risked being executed by the Sultan of Egypt.

Now in a quadruple bind, they faced the Portuguese forces.

• 6 Mediterranean carracks; 6 galleys (overall command of Amir Hussain)
• 4 carracks of Diu (Malik Ayyaz)
• 30 light galleys of Diu (Sidi Ali)
• 70–150 war-boats of Calicut (Kunjali Marakkar)

• 5 large naus: Flor de la mar (Viceroy's flagship; captain João da Nova), Espírito Santo (captain Nuno Vaz Pereira), Belém (Jorge de Melo Pereira), Rei Grande (Francisco de Távora), and Taforea Grande (Pêro Barreto de Magalhães)
• 4 smaller naus: Taforea Pequena (Garcia de Sousa), Santo António (Martim Coelho), Rei Pequeno (Manuel Teles Barreto) and Andorinha (Dom António de Noronha)
• 4 square rigged caravels: Flor da Rosa (António do Campo), Espera (Filipe Rodrigues), Conceição (Pero Cão), Santa Maria da Ajuda (Rui Soares)
• 2 caravels: Santiago (Luís Preto), – (Álvaro Pessanha)
• 2 galleys: São Miguel (Diogo Pires), São Cristóvão (Paio Rodrigues de Sousa)
• 1 brigantine: Santo António (Simão Martins)

As the wind turned by about 11:00 am, the royal banner was hoisted atop the Flor do Mar and a single shot fired, signaling the start of the battle.[31] At the general cry of Santiago! the Portuguese began their approach, with the galley São Miguel at the head of the formation, probing the channel. A general bombardment between the two forces preceded the grapple, and within the calm waters of the harbour of Diu, the Portuguese employed an innovative gunnery tactic: by firing directly at the water, the cannonballs bounced like skipping stones. A broadside from the Santo Espírito hit one of the enemy ships by the waterline, sinking it instantly.[32]

The black Portuguese broadsword remained popular aboard Portuguese armadas until the early 16th century.

As the carracks made contact, Hussain's flagship was grappled by the Santo Espírito. When their bowcastles crossed, a group of men led by Rui Pereira jumped onto the enemy bowcastle, and before the ships were secured, already the Portuguese had stormed all the way to midship. Before the flagship was dominated though, another Mamluk carrack came to its aid, boarding the Santo Espírito from the opposite side. Hussain had strengthened his forces with a great number of Gujarati soldiers, distributed across the ships, and the heavily armoured Portuguese infantry suddenly risked being overwhelmed. Rui Pereira was killed, but at this crucial moment, the Rei Grande slammed against the free side of Hussain's flagship, delivering direly needed reinforcements, which tipped the scales in favour of the Portuguese.[33]

Up on the crow's nests, Ethiopian and Turkish bowmen proved their worth against Portuguese matchlock crews. Many of the Muslim mercenaries otherwise "fled at the first sight of the Portuguese".[34]

Hussain had expected the Portuguese to commit their entire forces to the grapple, so he kept the light oarships back within the channel, to attack the Portuguese from behind when they engaged the carracks. Comprehending the stratagem, João da Nova maneuvered the Flor do Mar to block the channel entrance and prevent the oarships from sallying out. The compact mass of oarships provided an ideal target for Portuguese gunners, who disabled many ships that then blocked the path of the ones following. Unable to break through, the Zamorin's boats turned around after a short exchange, and retreated to Calicut. Throughout the course of the battle, the Flor do Mar fired over 600 shots.[35]

Meanwhile, the faster group of galleys and caravels grappled the flank of the stationary enemy galleys, whose guns were unable to respond. An initial Portuguese assault was repelled, but a Portuguese salvo threw three of the galleys adrift.[33]

Slowly but surely, the Portuguese secured most of the carracks, half-blinded by the smoke. Hussain's flagship was overpowered and many began jumping ship. The galleys were dominated, and the shallow caravels positioned themselves between the ships and the coast, cutting down any who attempted to swim ashore.[36]

Eventually, only a single ship remained – a great carrack, larger than any other vessel in the battle, anchored too close to shore for most of the deep-draught Portuguese vessels to reach. Its reinforced hull was impervious to Portuguese cannonfire and it took a continuous bombardment from the whole fleet to finally sink it by dusk, thus marking the end of the Battle of Diu.[36]

The Battle of Diu is considered as one of the most important battles in history. The author William Weir in his book 50 Battles That Changed the World, ranks this battle as the 6th most important in history, losing only to the Battle of Marathon, the Nika Rebellion, the Battle of Bunker Hill, the Battle of Arbela (Gaugamela) and the Battle of Hattin.[42] He says: "When the 15th century began, Islam seemed about ready to dominate the world. That prospect sank in the Indian Ocean off Diu."[43] The historian Rainer Daehnhardt says that this battle is compared only to the Battles of Lepanto and Trafalgar in terms of importance and legacy.[44] According to the scholar Michael Adas, this battle "established European Naval superiority in the Indian Ocean for centuries to come."[45]