The name arrived before the mansion did. In 1835, Lieutenant Colonel Henry Dumaresq — a war-wounded officer who had come to New South Wales as private secretary to his brother-in-law, Governor Ralph Darling — took up a vast sheep run on the tablelands and called it Saumarez, after his family's estate in Jersey. The Dumaresq line reached back to a Channel Islands seigneur of Saumarez, and the old name crossed the world to settle on Australian grass. Dumaresq did not enjoy it long. He died in March 1838 after a short illness, his early death blamed on his old war wound, and the run passed to his widow, Elizabeth Sophia. The grand house standing today came later, built by a different family on the foundations of his enterprise.

In 1874 the White family of Muswellbrook bought Saumarez and set about turning it into one of the largest and most successful properties in New England. Between 1888 and 1906 they raised the homestead itself, designed by architect J. W. Pender in the Federation Edwardian style and built by H. E. Elliott. The garden was the work of Mary White, who established it as carefully as the house was built. The Whites were not absentee owners; they were civic figures in Armidale, and their domestic continuity is exactly what gives the place its texture. F. J. White rode the wild gullies of his Aberfoyle cattle station collecting rainforest plants, many of which ended up sheltering in Mrs White's heated conservatory through the brutal New England winters.

Step beyond the thirty rooms and the estate keeps unfolding. Fifteen further buildings, dating from 1880 to 1910, ring the homestead: a cottage, a milking shed, stables and horse yards, a blacksmith's shop, even a slaughterhouse. Together they sketch the self-contained world of a great pastoral station, where almost everything needed could be made, mended or grown on site. Gold had drawn crowds here long before the mansion existed — when payable gold was found at Rocky River in the early 1850s, diggers flocked across the sheep run in numbers. The 10-hectare core preserved today was carved from a property that once ran to thousands of hectares, much of it still worked by the White family beyond the heritage precinct.

Saumarez is unusually legible because its family wrote so much down. When descendants of F. J. White gave the homestead precinct to the National Trust of Australia (NSW) in 1984, they handed over not just rooms but an archive — a rich photographic collection, White's letter-books, the station's work diaries, and oral histories from long-serving employees such as the Betts family, much of it now held at the University of New England Heritage Centre. That depth of record lets the house be read room by room, season by season. Listed on the State Heritage Register in 2002, Saumarez today hosts weddings, fashion shows and a film festival, proof that a preserved past need not be a frozen one — the household simply keeps finding new people to fill it.