The genteel agricultural town of Windsor was chosen by Charles Inglis, first overseas Bishop of the Anglican Church, over the larger military centre and colonial capital of Halifax (60 km to the southeast) so "...that it be well away from taverns and houses of ill fame,".
In April 1789, King George III gave Royal Assent to the establishment of King's Collegiate School, as well as to the establishment of the University of King's College - the first such honour to be bestowed upon any school in the British Empire. It is also claimed that Prince Edward, Duke of Kent took an interest in King's Collegiate School and University of King's College while stationed in Halifax as Commander-in-Chief, British North America.
In June 1890, the Anglican Diocese of Nova Scotia decided to establish a girl's school in Windsor to complement King's Collegiate School. Edgehill School opened in January 1891 and construction of a new building to house the new girls began in the following June.
In 1923 a disastrous fire swept through the campus causing irreparable damage to the main university buildings. With the encouragement of the Carnegie Foundation, which was promoting the consolidation of all Nova Scotian post-secondary institutions to Halifax around a nucleus formed by Dalhousie University, the University of King's College received funds to move into a newly built campus in Halifax. King's College remains an independent university, although its students enjoy affiliation privileges with Dalhousie. Its campus is located at the corner of Oxford Street and Cobourg Road, occupying the northwest corner of Dalhousie's Studley Campus.
Both King's Collegiate School and the newer Edgehill School remained on the Windsor campus and eventually expanded to include much of the 65 acre site, therefore better hosting the athletic tournaments which take place every year. In 1976 the governing bodies of both schools decided to amalgamate, and King's-Edgehill School was born.
In the past five years there have been major renovations of the school, ranging from the addition of a floor to the girls dormitory to the construction of the Ted Canavan Athletic Centre (opened in 2005), complete with a pool, double gym and well-equipped exercise facilities. The Fountain Performing Arts Centre was also completed recently to host musical performances and concerts.