By the time of Henry's death (1547) around half of the Irish houses had been suppressed; but many continued to resist dissolution until well into the reign of Elizabeth I, and some houses in the West of Ireland remained active until the early 17th century. In 1649, Oliver Cromwell led a Parliamentary army to conquer Ireland, and systematically sought out and destroyed former monastic houses. Subsequently, however, sympathetic landowners housed monks or friars close to several ruined religious houses, allowing them a continued covert existence during the 17th and 18th centuries, subject to the dangers of discovery and legal ejection or imprisonment.