The celebrated Shropshire historian, Eyton proclaimed of the Sandford family of The Isle that ‘No Shropshire family has a more splendid pedigree than the Sandfords of Sandford [q.v.] and the Sandfords of the Isle of Rossall’. With twelve members of the family having been knighted since the Conquest and a peerage granted to one of the family from the North Shropshire capital seat of Sandford in the nineteenth century, the Sandfords rank highly in terms of the old families of Shropshire. The situation of their ancestral seat, to the west of Shrewsbury is no less remarkable. Standing on high ground, the River Severn effectively forms a ring boundary around its approximately 600 acres of land. There is just a quarter of a mile across, from river bank to river bank, at its narrowest point at the southern end of the loop. The Isle, as it is usually known today, is also historically referred to as Up Rossall to distinguish it from Down Rossall or Rossall (q.v.).

The Isle had, in medieval times, formed a part of the possessions of the Rossall family whose male line came to an end with Sir John de Rossall in the fourteenth century. His two sisters became the heirs to his estates – Alice the wife of Philip de Englefield receiving Up Rossall (or The Isle) and so carrying it to that family. The moated site of her family mansion and adjacent site of a chapel, both located to the west of the present house at The Isle, can still be seen today.

The other sister, Eleanor, married into the Shrewsbury family of Sturry and inherited Down Rossall which continued to be owned by the Sturry successors until the mid seventeenth century. In the sixteenth century though, Alice Rossall’s descendant, Elizabeth, married Humphry Plowden of Plowden (q.v.). Their son Edmund became distinguished as the celebrated lawyer, whilst their daughter, Margaret, married Richard Sandford (d. 1588). Sandford was descended from Nicholas Sandford, a younger son of the Sandfords of Sandford (q.v.), who had established himself at The Lee near Whitchurch. Richard Sandford’s great-grandfather, William (d. 1509), had married Sibilla, daughter of Sir Fulke Sprenchose of Plaish and, through this marriage, added Edgton, near Bishops Castle to his landholding. This passed down the generations of the family.