The original owners of the Shire were the Aboriginal people of the Dharug, Kuringai and Darkingung language groups.
However, after about 50 years of European occupation, the Aboriginal people were forced from their home lands, destroying the vital relationship between land, culture, custom and ceremonies for Aboriginal people.
All that is left today are the many significant remnants of Aboriginal culture which stand as memorials to their long association with this country. These include:
- engravings on sandstone ridges
- rock shelters on the valley slopes containing cave paintings or drawing sites and archaeological deposits
- open campsites and grinding grooves on valley floors
- shell middens along tidal waterways
- scarred trees
Several towns in the shire have names derived from the Aboriginal language, for example, Berowra (place of many winds); Mt Kuring-gai (the local tribe); Dural (dooral - burning logs or standing dead trees, alight within); Berrilee (birra birra - pigs of the white settlers); Cowan (big water).
Access to remote areas was virtually impossible for the early European explorers due to a lack of facilities for road transport. Exploration was therefore confined to the rivers as the only accessible means of transport. The Hawkesbury River was one of the first regions explored in New South Wales after settlement in 1788.
Six weeks after the arrival of the first fleet, Governor Phillip led an exploration through Broken Bay in search of a large river to provide fertile land capable of cultivating crops for the colony. A branch of the Hawkesbury River was discovered, however due to a shortage of supplies, the party was forced to return. The Hawkesbury River was not discovered until the second expedition in the following year.
The second expedition, led by Governor Phillip, continued the exploration of the River. Upon discovering that the river was of a substantial size, Governor Phillip named it the Hawkesbury after the Baron of Hawkesbury. The party travelled for 16 days, passing Gentleman's Halt, Laughtondale and Wisemans Ferry, before reaching the fertile plains at Windsor. The River provided the major transport route for the farmers and became the lifeline for the delivery of produce to the growing colony. The shoreline also provided a good location for other commercial activities to establish, such as salt production, flour milling and boat building.
The lands within the present Hornsby Shire were not occupied in the early days of settlement. More accessible lands along the Parramatta and Hawkesbury Rivers were the preferred settlement areas. Settlement in the shire did not occur until the early nineteenth century, approximately twenty years after the arrival of the first fleet.
In 1825, Heneage Finch surveyed land from Castle Hill to Wisemans Ferry along the ridge to enable a road to be constructed, connecting Sydney with the Hunter Valley. The road was a continuation of Old Northern Road which had been constructed in 1817 from the Government Farm in Castle Hill to the present township of Galston. The new road was named the Great North Road and replaced the old Putty Road which linked Windsor, Putty and Bulga to the Hunter River which is located to the west of Hornsby Shire. Today the road is still used and is becoming a historical and tourist attraction.
The town of Hornsby, from which the shire gets its name, was named after police Constable Horne. In 1838, police Constables Thorn and Horne were rewarded with grants of land for the capture of a bushranger John MacMamara who had stolen a Parramatta dignitary's watch. Constable Thorn's land later became known as the suburb of Thornleigh whilst a village sprang up on Constable Horn's land which until the 1890s was known as the village of Hornsby. It was here that the first railway junction was built in 1893. There was considerable confusion for a number of years as the railway station was named Hornsby Junction and there was the village of Hornsby to the south. Eventually the village was renamed Normanhurst and the railway station became Hornsby. Because the main northern railway line and the North Shore line joined at Hornsby, it developed as a railway town.
Hornsby Shire was incorporated in March, 1906. A Provisional Council of five members was appointed by the State Government to initially control the Shire. The first meeting was held on 14 June, 1906, at which time Mr O.G. Roberts was elected the first Shire Mayor. The State credited the Council with a budget of 20 pounds.
In November of 1906 of the first shire elections were held. The shire's population (4700) had previously been divided into three Wards, of similar population but not area. Two Councillors were elected from each Ward and Councillor J.C. Hunt became the Mayor. At the second election in 1910 the number of Councillors increased to nine with the election of an additional representative from each Wards. This system remained until the 2004 Local Government Elections which introduced a popularly elected Mayor in addition to three Councillors elected by residents in each of three Wards.
Early development within the shire followed the railway lines and ridge tops. The introduction and eventual dominance of the motor car allowed urban growth in areas not serviced by the railway.
Since the end of the Second World War there has been a period of rapid growth within the shire population growing from 30,500 in June 1945 to an estimated 140000 in June 1998.
The conservation of the shire's Aboriginal and European heritage is important and Hornsby Council has undertaken a number of strategies to assist this being achieved.