The Castle Hill Rebellion of 1804 was a rebellion by convicts against colonial authority in the Castle Hill area of the British colony of New South Wales. The rebellion culminated in a battle fought between convicts and the Colonial forces of Australia on 5 March 1804 at Rouse Hill, dubbed the Second Battle of Vinegar Hill after the first one of 1798 Battle of Vinegar Hill in Ireland. It was the first and only major convict uprising in Australian history suppressed under martial law.
On 4 March 1804, according to the ‘official’ accounts 233 convicts led by Philip Cunningham (a veteran of the Irish Rebellion of 1798, as well as mutiny on the convict transport ship Anne) escaped from a prison farm intent on “capturing ships to sail to Ireland”. In response, martial law was quickly declared in the Colony of New South Wales. The mostly Irish rebels, having gathered reinforcements, were hunted by the colonial forces until they were sequestered on 5 March 1804 on a hillock nicknamed Vinegar Hill. Under a flag of truce, Cunningham was arrested and troops charged and the rebellion was crushed by the raid. Nine of the rebel leaders were executed and hundreds were punished before martial law was finally revoked on 12 March 1804.