The Principality of Marlborough was a short-lived micronation established in 1993 located at near Marlborough, Queensland, Australia, about 106 km (66 mi) north of Rockhampton.

Flags

In 1993, George Muirhead declared himself to be the Duke of Marlborough and conducted a ceremony under four flags representing his ancestors five generations. The flags were the Australian flag, the Aboriginal flag, the Scottish flag and the United Nations flag.