Dorothy Osborne, the daughter of a staunch Royalist, met William Temple, whose father favoured Oliver Cromwell, towards the end of the English Civil War. Despite strong opposition from both families, the couple embarked on a seven-year courtship, mostly through letters - many now found in the British Library. When they eventually married, William went on to achieve a place in history as a diplomat and gifted essayist. But along with worldly success...