In 1818, John Oxley and the members of his second inland expedition were the first Europeans to enter the Warrumbungles. After following the westward flowing Macquarie River till it disappeared into the Marshes, he travelled northeast to where he saw the jagged mountains on 13 July. He named them “Arbuthnot’s Range”. By 11 August he was close enough to send a party to climb a nearby peak, which he called Mount Exmouth. He tried to cross the Pilliga to reach the distant Nandewar Ranges which he could see from there. However he got bogged and gave up, finally heading east and reaching the coast at Port Macquarie.
His reports of fertile plains brought European invaders from the coast whose stock took over the water holes and ate the grass that the native animals and Aboriginal people had depended on. Squatters took up and cleared the flat lands of the lower levels for farming and wool-growing well before the land was gazetted for such uses. When the law caught up, legislation required that these farmers build fences, even in the more inaccessible areas.
The area that is now National Park was a farm. The flatter ares were cleared. Sheep were grazed and crops were grown. The delicate food webs were disturbed with the eradication of the dingo and the introduction of foxes, rabbits, goats and pigs.
In the 1930’s some members of the Sydney Bushwalkers began to visit the mountains to explore and to climb the rugged mountains. These included Dot Butler, Dr Dark and Myles Dunphy who recommended that it become a National Park in 1937. This was finally put into effect in 1953 when nearly 4000 hectares of the property “Wambelong” was given up by leaseholder A J Pincham to be placed under the management of a Trust. National Parks and Wildlife Service took over management in 1967, further acquisitions have been made and the Warrumbungle National Park now totals over 23 606 hectares.