Dirk Hartog (Dutch pronunciation: [dɪrk ˈɦɑrtɔx]; baptized 30 October 1580, Amsterdam – buried 11 October 1621, Amsterdam) was a 17th-century Dutch sailor and explorer. Dirk Hartog's expedition was the second European group to land in Australia and the first to leave behind an artifact to record his visit,the Hartog plate. His name is sometimes alternatively spelled Dirck Hartog or Dierick Hartochsz. Ernest Giles referred to him as Theodoric Hertoge. Born into a seafaring family, at the age of 30 he received his first ship's command, and spent several years engaged in successful trading ventures in the Baltic and Mediterranean seas.

Discovery in Western Australia

In 1616 Hartog gained employment with the Dutch East India Company (VOC), and was appointed master of a ship (the Eendracht, meaning "Concord" or "Unity") in a fleet voyaging from the Netherlands to the Dutch East Indies.

Hartog set sail in January 1616 in the company of several other VOC ships, but became separated from the others in a storm, and arrived independently at the Cape of Good Hope (later to become the site of Cape Town, South Africa). Leaving there, Hartog set off across the Indian Ocean for Batavia (present-day Jakarta), utilising (or perhaps blown off course by) the strong westerly winds known as the "Roaring Forties" which had been earlier noted by the Dutch navigator Henderik Brouwer as a quicker route to Java.