Since the early 20th century, the Art Gallery of Ontario has been expanded a number of times, and the original manor makes up only a small part of the structure.

In 1970, The Grange was designated a National Historic Site of Canada in recognition of the house's significance to the history of Toronto.

The north section of the property was sold to Bishop Strachan in 1828, to be used for the establishment of King's College, an Anglican university.

Sarah Anne Robinson was born in Lower Canada in 1789 to a loyalist family who had previously moved north from Virginia after the American Revolution.

The two met through Sara Anne's older brother Peter Robinson and settled at The Grange (so named for the Boulton family estate in Lincolnshire, England) in 1817.

[3] Sarah Anne quickly established herself as a superior hostess and The Grange became a central site for the social and political happenings of early Toronto.

D’Arcy Boulton made his living running a dry good store and obtaining three governments posts.

William, however, was fond of gambling and Harriette and her mother-in-law, Sarah Anne, spent much time trying to keep The Grange in Boulton hands.

Smith was a proud supporter of the arts in Toronto and founded journals and encouraged young artists to paint Canadian subjects.

Between Reid and Edmund Walker (prominent banker and champion of the arts), a campaign was established to raise money for the gallery scheme.

From the early days of the Art Museum of Toronto until the restoration of the 1960s, The Grange underwent a variety of changes, including electrification and the inclusion of an apartment for a live-in caretaker.

This was a time in Ontario of increased interest in heritage preservation and so the Junior Women's Committee raised $650 000 for a restoration project.

[3] Designated by the City of Toronto under the Ontario Heritage Act by By-law 130-91[4] Today, The Grange houses the Norma Ridley Members’ Lounge and exhibit spaces.

The original house, designed by an unknown architect, was two storeys high, 60 by 40 feet (18 m × 12 m) in area, with a low hipped roof containing a circular window.

This crest is a visual play on the name Boulton, as it shows a barrel pierced by an arrow, or bolt, with a hogshead of wine or tun.

The family motto — "Dux vitae ratio" ("The guide to life is reason") — rests below the crest, always reminding the Boultons of their British ancestry.

Several images of The Grange show a domed glass conservatory on the east side of the house, which would have been filled with plants readily available from catalogues.

William Boulton won prizes at the 1844 Toronto Horticultural Society Show for geraniums, roses, greenhouse plants and pansies.

With the sale of the southern part of the property in the mid-19th century, a new entrance to The Grange was created, which included a lodge — home to William Chin, the butler, and his family.