Lenaert Jacobszoon was a captain of the Dutch East India Company

Dutch East India Company

The Dutch East India Company was a chartered company established in 1602, when the States-General of the Netherlands granted it a 21-year monopoly to carry out colonial activities in Asia...

 who, on 31 July 1618 in the vessel Mauritius, sighted North West Cape

North West Cape

North West Cape is a large peninsula of land in the north west coast of Western Australia. Cape Range runs down the spine of the peninsula and Ningaloo Reef runs along the western edge...

 in the north-west of Western Australia

Western Australia

Western Australia is a state of Australia, occupying the entire western third of the Australian continent. It is bounded by the Indian Ocean to the north and west, the Great Australian Bight and Indian Ocean to the south, the Northern Territory to the north-east and South Australia to the south-east...

 mistakenly believing it to be a large island. He also named the Willems River and the Jocob Remmessens River (presumed to be Yardie Creek) in the same voyage.

On board the ship was supercargo

Supercargo

Supercargo is a term in maritime law that refers to a person employed on board a vessel by the owner of cargo carried on the ship...

 Willem Janszoon

Willem Janszoon

Willem Janszoon , Dutch navigator and colonial governor, is probably the first European known to have seen the coast of Australia. His name is sometimes abbreviated to Willem Jansz....

, former captain of the Duyfken

Duyfken

Duyfken was a small Dutch ship built in the Netherlands. She was a fast, lightly armed ship probably intended for shallow water, small valuable cargoes, bringing messages, sending provisions, or privateering...

, who wrote to the Dutch East India Company in Amsterdam

Amsterdam

Amsterdam is the largest city and the capital of the Netherlands. The current position of Amsterdam as capital city of the Kingdom of the Netherlands is governed by the constitution of August 24, 1815 and its successors. Amsterdam has a population of 783,364 within city limits, an urban population...

 about the discovery of an island during this yoyage. Also on board was 25-year-old Anthony van Diemen

Anthony van Diemen

Anthony van Diemen , Dutch colonial governor, was born in Culemborg in the Netherlands, the son of Meeus Anthonisz van Diemen and Christina Hoevenaar. In 1616 he moved to Amsterdam, in hope of improving his fortune as a merchant; in this he failed and was declared bankrupt...

 who was later to push for the further exploration of the southern land and after whom Van Diemen's Land

Van Diemen's Land

Van Diemen's Land was the original name used by most Europeans for the island of Tasmania, now part of Australia. The Dutch explorer Abel Tasman was the first European to land on the shores of Tasmania...

(Tasmania

Tasmania

Tasmania is an Australian island and state. It is south of the continent, separated by Bass Strait. The state includes the island of Tasmania—the 26th largest island in the world—and the surrounding islands. The state has a population of 507,626 , of whom almost half reside in the greater Hobart...

) was named.