Jacob Willekens or Wilckens (1571-1633) was a Dutch admiral and privateer who commanded the different fleets for the Dutch West Indies Company during the 16th and 17th century. His most well-known success was undoubtedly the conquest of San Salvador de Bahia, the then capital of Brazil. His fleet, which included Dutch corsair Piet Hein as vice admiral, departed from Texel on December 22, 1623 with between 26-36 ships and 3,300 sailors towards South America. At the beginning of June 1624, they began their attack from sea and soon captured the Portuguese stronghold with little resistance. They occupied Bahia for over a year before the local population took up arms under acting governor Matias de Albuquerque and Archbishop Dom Marcos Teixeira who eventually expelled them with the help of a combined Spanish-Portuguese fleet numbering 52 warships and 12,000 soldiers in May 1625. This was the first major WIC privateering expedition to the region.
He would also participate in an attack on Rio de Janeiro with Hein in 1626, but after a dispute over who would be in command, the two separated with Willekens returning to Amsterdam. After a successful attack on Manilla, Willekens died on Ternate in 1633.