Portuguese fidalgo Diogo Lopes de Sequeira (1465–1530) served as Captain-major of the Portuguese Gold Coast (1503–1506) before a commission to analyse the trade potential in Madagascar and Malacca.
He set sail from Lisbon in April 1508 with four ships and arrived in Cochin, India, more than a year later. After four months there, he moved on to Malacca in August 1509, with Ferdinand Magellan among the men under his command.
On the way, he landed in Sumatra, where he erected two stone pillars registering Portugal's claim to the island.
He arrived at Malacca on 11 September 1509. He left the following year when he discovered that Sultan Mahmud Shah was planning his assassination.
The loss of sixty of his men as he extracted himself from Malacca gave Afonso de Albuquerque the excuse to return with a stronger force and conquer the city.
Sequeira was subsequently governor of Portuguese India (1518–1522), and in 1520 led a military campaign into the Red Sea, which resulted in the first legitimate Portuguese embassy to Ethiopia. He eventually returned to Portugal and died in his birthplace, Alandroal.
Sources:
Encyclopedia Britannica