Jørgensen was born as the second son of the royal watchmaker Jurgen Jurgensen. Two of his brothers were watchmakers; the elder, Urban Jürgensen, was of international renown. At the age of 15, Jørgensen finished school and was apprenticed to Captain Henry Marwood of the British collier Janeon. In 1799, he sailed to Cape Town and from there in 1800 to Port Jackson, the new British colony in Australia and to New Zealand. In 1801, he joined the crew of the Lady Nelson. As a member of that crew, Jørgensen was present at the establishment of the first settlements of Risdon Cove and Sullivans Cove in Van Diemen's Land, as Tasmania was then called. He has been called the founder of the city of Hobart Town, now Hobart, and is still a local hero.
