Saltemersc 1086 (Domesday Book). "Salty or brackish marsh". Old English salt + mersc.
"A Dictionary of English Place-Names", Oxford University Press
Saltmarshe Hall, set in a beautifully wooded surround, is typical of an estate landscape. Although completely moulded by man, the house mellows with the yellow cover of rape blossom and the varied shades of green leaf and creates a rarely seen haven on the lower Ouse, as most trees have been felled by farmers.