Australian Dictionary of Biography

Willem Janssen (flourished 1603-1628), mariner, of Amsterdam, was, according to Valentijn, a foundling. He received at least enough education to enable him to write a good hand and to become expert in navigation. He is first distinguishable from his many namesakes when, in December 1603, he sailed from Holland for the East as skipper of the small yacht Duyfken in the fleet of van der Hagen. In 1605-06 he took part as her skipper in the first discovery of any part of the Australian coastline when he examined the east coast of the Gulf of Carpentaria from 11°S to 14°S. On his return from that expedition he was desultorily employed as a skipper for several years and served for a time in the squadron commanded by Jan Roossengin. In January 1611 he was appointed an upper-merchant and sailed for home in that grade. 

He returned to the East in November 1612 and served in Moluccan waters as an upper-merchant and for a time as governor or commandeur of Fort Henricus on Solor. At the end of 1616 he again went home as upper-merchant and in July 1617 took his discharge. In August he re-enlisted in his former grade but with the promise of early employment as a vice-governor or commandeur at sea. In January 1618 he set out in the Mauritius for Java, and on 31 July called at Cloates Land, which he reported as a new discovery, being ignorant of Mibaise's earlier sighting of it. His landing party saw, near North-West Cape, footprints and smoke signals: the earliest evidence that Eendracht's Land was inhabited. On reaching Jacatra he was called into consultation by the governor-general and in March 1619 was appointed to the Council of the Indies. He took part in the operations in which Coen relieved the fort and destroyed the town of Jacatra, and soon afterwards sailed to Tiku where he captured four ships of the English East India Co., which had aided the Javanese. For his part in this he was decorated with a chain of honour.

In June 1620 he was appointed vice-admiral to Robert Adams of an Anglo-Dutch 'Fleet of Defence' against the Iberian powers. The fleet made an unprofitable cruise and next year the positions of the senior officers were reversed, Janssen becoming admiral. When the English withdrew from these operations he continued them for a time as admiral of the Dutch ships, but eventually retired to Batavia. In October 1623, the government of Banda having fallen into disorder, he was appointed governor there and took up the office in December. He soon restored the place to order and established churches and schools, financing the schools by a lottery. He served there until February 1627, then returned to Batavia and was appointed commandeur of a fleet for a voyage to Persia. He returned in June 1628, and soon afterwards, when the Mataram laid siege to Batavia, he lent Coen valuable support in its defence, though by reason of his age he was not permitted to face the enemy at the head of troops. In November 1628 he was sent home as one of the three joint-commanders of a fleet which reached Holland in July 1629. On arrival he was sent to report to the States-General and the stadtholder on the state of the Indies, and thereafter he drops out of sight. It does not appear that he ever married.

Janssen was a good disciplinarian, diligent, unassuming and good-tempered. Although he appears to have lacked outstanding ability, his qualities made him a valuable executive officer. By reason of a trick of his speech, he had from contemporaries the nickname 'Ik zeg, ik zeg' (I say, I say).