Castle Hill is located in the Hills District, Sydney, NSW, Australia about 30 kilometres north-west of Sydney GPO. It is the headquarter of the Hills Shire local government. The history of Castle Hill, NSW, Australia is as old as the hills themselves. The land which is now called Castle Hill was formerly occupied by the Bidjigal people who are a subgroup of the Aboriginal person. The Bidjiga under the leadership of Pemulwuy settled in the area following a resistance war against local inhabitants. The Bidjigal people are today remembered through the Bidjigal Reserve which stretches out in the suburbs of West Pennant Hills, North Rocks, Baulkham Hills and Castle Hill

The region came fell under European settlement with the first group of with the first group arriving in 1791 under the leadership of Governor Phillip. The group travelled from Parramatta and reached Castle Hill through the Aboriginal trails which are today covered by the Old Northern and Windsor roads. Governor Phillip and his entourage were looking for new land for settlement and farming to have food for the struggling new colony. 

The place known as Castle Hill came to be called so during the reign of Governor King who started a prison farm called Government Farm 3, in the region on 8 July 1801. He named the place Castle Hill on 1 March 1802. Many of the prisoners who worked on Government Farm 3 were Irish Catholics many of who had been brought in 1798 for subversive activity. Baron Verincourt de Clambe, a Frenchman was the first free settler in Castle Hill and was given a 200-acre grant in 1802. It is de Clambe’s house that was called the “The Castle” due to his noble status, and that is how the place got the name Castle Hill.

The Castle Hill convict rebellion is a notable event in the history of Castle Hill, NSW, Australia and was sparked off by prisoners leading to what came to be called “The Second Battle of Vinegar Hill”. The rebellion started on March 4, 1804, after the convicts overpowered the guards. After torching a hut at the farm, the prisoners matched towards Parramatta to signal their counterparts at Hawkesbury. However, the group was later overpowered and by the Red Coats, the disciplined English troops who killed many of the prisoners. 

The Rogans Hill railway line ran through the Castle Hill to Parramatta and was built to transport farm produce to the market. It was later closed down in 1932 due to stiff competition from trucks, buses, and cars.

Among the notable landmarks in Castle Hill include the Castle Hill House constructed in 1844 and located on Northern Road which bears a heritage listing of a local government, the public school built in1879 which is also located on Old Northern Road. Others are former parsonage constructed in 1866 and located on Parsonage Road and the old church which is located on Old Northern Road which has since been converted into a commercial place. From the post-war period up to 1968, the Castle Hill was occupied by Nobel Prize winner Patrick White and his partner Manoly Lascaris who lived in a house called “Dogwoods” located at 74 Showground Road. They undertook farming on several acres of land at the site.