The manor of St Catherine belonged to Prior Cantlow of Bath Abbey in medieval times. It takes its name from the Church of St Catherine beside the manor house. When the house was not occupied by the monks, it was leased. In 1536, the lease was to Thomas Llewellyn, who remained as the tenant after the Dissolution of the Monasteries. Henry VIII granted the manor to his tailor, John Malte, in 1546. Part of the condition of the gift was that he adopt the king's illegitimate daughter Ethelreda Malte. Ethelreda inherited the house and married John Harington. After Ethelreda's death in 1551, Harrington married again. His son from this marriage was another John Harington who grew up and became a courtier of Elizabeth I and invented the first flush toilet. He spent most of his time at his principle seat at nearby Kelston and, in 1591, sold St Catherine's Court to John Blanchard. His son, William Blanchard, remodelled the house. His initials appear in the plasterwork frieze of a bedroom. The Blanchard family lived at the court for several generations. In 1610, the porch was added and a terraced garden laid out. The house passed by marriage to the Parry family but was not maintained, and the fabric of the building was declining by the 18th century, when half of the building was used by a tenant farmer.