inlet of the Timor Sea, having a width of 200 miles (320 km) and indenting the north coast of Australia for 100 miles. Although its western limit is generally agreed to be Cape Londonderry in Western Australia, its eastern limit is variously placed between Cape Scott and Point Blaze in Northern Territory.

The Ord, Durack, Pentecost, and Forrest rivers enter the Joseph Bonaparte Gulf via an estuarine division called Cambridge Gulf, which is the site of Wyndham, the area's principal port. The Victoria River flows into the gulf's Queen's Channel and the Fitzmaurice River into Keyling Inlet. Aboriginal reserves are on the east and west shores. The gulf was entered (1644) by the Dutch navigator Abel Tasman. In 1803 it was visited by Nicolas Baudin, a Frenchman who named it after the eldest brother of Napoleon I. The name was discarded by Capt. Phillip Parker King of the Royal Navy when he conducted a coastal survey in 1817, but it was revived during World War II.