Eureka Jack Mystery

Since 2012, various theories have emerged, based on the Argus account of the Battle of the Eureka Stockade and an affidavit sworn by Private Hugh King three days later as to a flag being seized from a prisoner detained at the stockade, that a Union Jack, known as the Eureka Jack may also have been flown by the rebels. Readers of the Argus were told that: "The flag of the diggers, 'The Southern Cross,' as well as the 'Union Jack,' which they had to hoist underneath, were captured by the foot police."

Ray Wenban depicted the Eureka Jack in a 1958 pictorial history series for students. In honour of the 160th anniversary of the battle in 2014, the Australian Flag Society released "Fall Back with the Eureka Jack," which illustrates Gregory Blake's two-flag theory in folk art.