The duchy of Lorraine was one of the most extensive and opulent of the minor States of the German empire. Admirably situated upon the Rhine and the Meuse, and extending to the sea, it embraced over ten thousand square miles, and contained a population of over a million and a half. The duke, Francis Stephen, was the heir of an illustrious line, whose lineage could be traced for many centuries. Germany, France and Spain, united, had not sufficient power to induce Maria Theresa to reject Francis Stephen, the grandson of her father's sister, the playmate of her childhood, and now her devoted lover, heroic and fascinating, for the Spanish Carlos, of whom she knew little, and for whom she cared less. Ambition also powerfully operated on the very peculiar mind of Maria Theresa. She had much of the exacting spirit of Elizabeth, England's maiden queen, and was emulous of supremacy which no one would share. She, in her own right, was to inherit the crown of Austria, and Francis Stephen, high-born and noble as he was, and her recognized husband, would still be her subject. She could confer upon him dignity and power, retaining a supremacy which even he could never reach. The emperor was fully aware of the attachment of his daughter to Francis, of her inflexible character; and even when pretending to negotiate for her marriage with Carlos, he was conscious that it was all a mere pretense, and that the union could never be effected. The British minister at Vienna saw very clearly the true state of affairs, and when the emperor was endeavoring to intimidate England by the menace that he would unite the crowns of Spain and Austria by uniting Maria and Carlos, the minister wrote to his home government as follows: "Maria Theresa is a princess of the highest spirit; her father's losses are her own. She reasons already; she enters into affairs; she admires his virtues, but condemns his mismanagement; and is of a temper so formed for rule and ambition, as to look upon him as little more than her administrator. Notwithstanding this lofty humor by day, she sighs and pines all night for her Duke of Lorraine. If she sleeps, it is only to dream of him; if she wakes, it is but to talk of him to the lady in waiting; so that there is no more probability of her forgetting the very individual government, and the very individual husband which she thinks herself born to, than of her forgiving the authors of her losing either."