Holcombe Manor was built in 1887 as a house by the first mayor of Chatham, George Winch (September 20, 1842 – February 22, 1914), for him and his wife Mary Clarke Bluette to live in.
The lots were the house itself, the local football ground, Chatham Town F.C., and the surrounding woodland.
In 1920 the house became home to Chatham Grammar School for Boys, after which more buildings were built to accommodate students.
After a consultation with pupils, staff and parents the name "Holcombe Grammar School" was selected.
During the late fifties, pre-fabricated buildings were erected in the grounds to serve as classrooms.