The coastline of Australia was gradually revealed and charted over nearly two centuries of exploration by Dutch and English explorers. By the beginning of the nineteenth century there remained one last stretch of the south coast of the island continent that had not been charted and which was represented on maps as a dotted line. Two countries, France and England, would outfit expeditions to discover and explore this unknown coast.
The Dutch had begun the discovery of a southern landmass in 1606 when they sent Captain Willem Janszoon in the Duyfken east from Java to explore the New Guinea coastline. He traced this south, diverted by the shoals of Torres Strait, and charted the west coast of Cape York Peninsula. Between 1616 and 1628 the ships and captains of the Dutch East India Company (VOC) would chance upon sections of the Western Australian coastline, following it north to Java. In 1627 the Gulden Zeepard under Captain Frans Thyssen charted part of the south coast east from Cape Leeuwin. He sailed only as far as the islands south of present day Ceduna in South Australia. Then in 1642 Abel Tasman was sent out by the VOC to determine the size of the south land and hopefully discover a route to rich lands useful for trade purposes. Tasman discovered the southern part of Tasmania, naming it Van Diemen's Land. The dotted line of the 'unknown coast' joins Thyssen's discovery with Tasman's. The Dutch called the continent they discovered New Holland.
In 1770 the Englishman James Cook in his ship Endeavour charted the east coast of the continent naming it New South Wales. In 1799 George Bass and Matthew Flinders circumnavigated Van Diemen's Land, proving it was an island and distinct from New South Wales. There now remained only a small section of coastline to discover: the unknown coast.