This war took place upon the backdrop of the Ethiopian-Adal War. Ethiopia had been invaded in 1529 by the Somali Imam Ahmed Gragn. Portuguese help, which was first asked by Emperor Lebna Dengel in 1520 to help defeat Adal while it was weak, finally arrived in Mitsiwa on February 10, 1541, during the reign of Emperor Galawdewos. The force was led by Cristóvão da Gama and included 400 musketeers, several breech-loading field guns, and few Portuguese cavalry as well as a number of artisans and other non-combatants.
War begins
Major hostilities between Portugal and the Ottoman Empire began in 1538, when the Ottomans assisted the Sultanate of Gujarat with about 80 vessels to lay siege to Diu, which had been built by the Portuguese in 1535. The Ottoman fleet was led by Suleiman I's governor of EgyptSuleiman Pasha, but the attack was not successful and the siege was lifted. The Portuguese under Estêvão da Gama organized an expedition to destroy the Ottoman fleet at Suez, leaving Goa on December 31, 1540 and reaching AdenJanuary 27, 1541. The fleet reached Massawa on February 12, where Gama left a number of ships and continued north. The Portuguese then sacked the Ottoman port of Suakin. Reaching Suez, he discovered that the Ottomans had long known of his raid, and foiled his attempt to burn the beached ships. Gama was forced to retrace his steps to Massawa, although pausing to attack the port of El-Tor.
Ethiopian Campaign
At Massawa, governor Estevão da Gama responded to an appeal by the Bahr Negus to assist the Christian Ethiopian Empire against invading Adalite forces. An expeditionary corps of 400 men was left behind, commanded by the governors' brother, Cristóvão da Gama. On February, 1542, the Portuguese were able to capture an important Adalite stronghold at the Battle of Baçente. The Portuguese were again victorious at the Battle of Jarte, killing almost all of the Turkish contingent. However, the Gragn then requested aid from the Ottoman governor of Yemen in Aden, who sent 2000 Arabian musketeers, 900 Turkish pikemen, 1000 Turkish foot musketeers, some Shqiptarfoot soldiers and Turkish horsemen. In the Battle of Wofla, Somali and Turkish forces defeated the Portuguese, Gama was captured and killed by Gragn himself upon refusing to convert to Islam. Gelawdewos was eventually able to reorganize his forces and absorb the remaining Portuguese soldiers and defeated Gragn at the Battle of Wayna Daga, marking the end of the Ethiopian-Adalite war.
Persian Gulf campaigns
Elsewhere in the Indian Ocean naval combat was also intense. In 1547 the Admiral Piri Reis took command of the Ottoman-Egyptian fleet in the Indian Ocean and on 26 February 1548 recaptured Aden, in 1552 sacked Muscat. Turning further east, Piri Reis failed to capture Hormuz, at the entrance of the Persian Gulf. Following these events, the Portuguese dispatched considerable reinforcements to Hormuz, and the following year defeated an Ottoman fleet at the Battle of the Strait of Hormuz. In 1554 the Portuguese soundly defeated an Ottoman fleet led by Seydi Ali Reis in the Battle of the Gulf of Oman and in 1557 the Ottoman captured the port of Massawa to the province of Habesh. In 1559 the Ottomans laid siege to Bahrain, which had been conquered by the Portuguese in 1521 and ruled indirectly since then, but the forces led by the Governor of Al-Hasa were decisively beaten back. After this, the Portuguese effectively controlled the entirety of the naval traffic in the Persian Gulf. They raided the Ottoman coastal city ofAl-Katif during this time, in 1559.
Aftermath
Unable to decisively defeat the Portuguese or threaten their shipping, the Ottomans abstained from further substantial action in the near future, choosing instead to supply Portuguese enemies such as the Aceh Sultanate. The Portuguese on their part enforced their commercial and diplomatical ties with Safavid Persia, an enemy of the Ottoman Empire. A tense truce was gradually formed, wherein the Ottomans were allowed to control the overland routes into Europe, thereby keeping Basra, which the Portuguese had been eager to acquire, and the Portuguese were allowed to dominate sea trade to India and East Africa. The Ottomans then shifted their focus to the Red Sea, which they had been expanding into previously, with the acquisition of Egypt in 1517, and Aden in 1538.
