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 in 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 the first elections were held. The Shire's population (4,700) had previously been divided into three wards of similar population, with two councillors elected from each. Councillor J.C. Hunt became the first mayor (which was called the Shire President until 1993). At the second election in 1910 the number of councillors increased to nine, with an extra representative from each ward.
For almost 100 years the mayor was elected by the councillors each year, but in 2004 the mayor became popularly elected for a four-year term following a referendum of the Shire’s residents. There are still three representatives from each ward, bringing the total number of council members to 10.
Up until May 2016, the Hornsby Shire Council area covered approximately 510 square kilometres, including 6,000 hectares of public bushland for which Council was responsible. The Shire extended from Brooklyn in the north, to Wisemans Ferry and Glenorie/Dural in the west, Wahroonga in the east and Epping in the south.
In May 2016 the NSW Government transferred the former Hornsby Shire Council area south of the M2 Motorway to the City of Parramatta Council and abolished Hornsby’s then existing three-ward structure.
By proclamation on 23 January 2017, the State Government established a new three ward structure for the Hornsby Shire Council area which took effect from the 9 September 2017 Council election.
Homes of Hornsby Shire Council Patricia Dewey (2007).
The first permanent Council Chambers built in 1916 cost ratepayers £1,650. In 1956 the handsome two storey building on Peats Ferry Road was worth £27,500.
The first office of Council was at the School of Arts building, which became part of the Hornsby Home Science School when the department purchased the building. Not long after its formation in 1906, Council applied for land adjacent to the local drill hall. Land along Peats Ferry Road had been set aside for 'Government purposes'. The drill hall later became the court house and eventually classrooms for the Hornsby Boys Public School and on occasions the Hornsby Home Science School.
Arrangements were made in 1907 to lease from James Glynn, the Hornsby Stationmaster at the time, a cottage in Jersey Street Hornsby. The rent paid was 16/- per week. The cottage became the first official Council Chamber and Shire Office. In 1915 an application for the present site of the Council Chambers was successful and so the first permanent headquarters of the shire were erected as a single storey building and occupied as such on 2 January 1916. Contractor was A. H. Ponton, a well known resident of Hornsby.
In 1930 the top storey at a cost of £4,650 was added by Basil Harris, another well known builder and resident of Hornsby. The building was now large enough to accommodate a public gallery of fifty, which was located upstairs. This left the lower floor available for offices. However, by the mid 1960s and with the expansion of the number of Council departments there came a need to extend the premises again. The problem was how to do this on such a small site.
Towards the end of the 1960s a decision by Council was made to build a much needed library as well as new Administration Offices. Council needed land to the north facing Peats Ferry Road. A piece of Council owned land was exchanged which adjoined the Education Department's property facing Jersey Street for land on which the original Hornsby Drill Hall stood to the north of Council premises. The Department of Education was not interested in moving the Drill Hall so it was left to Council to move the building so that the extension could go ahead. After much discussion it was decided to move the building to Kenley Park at Normanhurst where the Drill Hall stands today as the Museum and Meeting Place of the Hornsby Shire Historical Society.
With the site cleared extensions to the premises began. However, there was a great deal of excitement in September 1970 when excavators preparing the ground for the foundations of the new building unearthed an old cannon buried eight feet below the surface. Although no one seemed to know where the cannon had come from former, long time residents of the Shire recalled that a cannon had at one time stood at the side of the Drill Hall and then in front of the Council premises.
At the opening of the new Central Library and Administration Offices on 29 April 1972 Major R. H. Wearne, Officer Commanding Sydney Area Workshops, presented a model of the cannon to the Council. This model is currently displayed in Hornsby Shire Library. The original cannon was 'claimed' by Victoria Barracks.
In 1994 when the Administration premises again became too small, the Central Library was relocated to George Street Hornsby and the old library premises now form part of the Administration Offices.
