Accompanying the First Fleet to Port Jackson were three companies of marines totalling 212 men under the command of Major Robert Ross, to guard the fledgling colony of Sydney and that of Norfolk Island, which had been established on 6 March 1788 to provide a food base and investigate supply of masts and flax for canvas for the Royal Navy. In 1790 the Second Fleet arrived, and the marines were relieved by a new force which was created specifically for service in the colony of New South Wales. With an average strength of 550 men, it was known as the New South Wales Corps. The first contingent of 183 men, under Major Francis Grose, arrived in New South Wales in June 1790. They were subsequently expanded with further contingents from Britain as well as free settlers, former convicts and marines who had discharged in the colony. Throughout the mid-1790s the New South Wales Corps was involved in "open war" along the Hawkesbury River against the Daruk people. Between 1786 and 1792 an ad hoc volunteer unit known as the New South Wales Marine Corps from the British Royal Navy was created to guard the convicts aboard the First Fleet to Australia and to preserve "subordination and regularity" in the penal colony in New South Wales.