In exile at Briihl Mazarin saw the mistake he had made in isolating himself and the queen, and that his policy of balancing every party in the state against each other had made every party distrust him. So by his counsel the queen, while nominally in league with De Retz and the parliamentary Fronde, laboured to form a purely royal party, wearied by civil dissensions, who should act for her and her son's interest alone, under the leader ship of Mathieu Mole, the famous premier president of the parle ment of Paris. The new party grew in strength, and in January 1652, after exactly a year's absence, Mazarin returned to the court. In order to promote a reconciliation with the parlement of Paris Mazarin had again retired from court, this time to Sedan, in August 1652, but he returned finally in February 1653. He had retrieved his position by founding that great royal party which steadily grew until Louis XIV. could fairly have said "L'Etat, c'est moi." As the war had progressed, Mazarin had steadily followed Richelieu's policy of weakening the nobles on their country estates. Whenever he had an opportunity he de stroyed a feudal castle, and by destroying the towers which commanded nearly every town in France, he freed such towns as Bourges, for instance, from their long practical subjection to the neighbouring great lord.
The Fronde over, Mazarin had to build up afresh the power of France at home and abroad. Beyond destroying the brick-and mortar remains of feudalism, he did nothing for the people. But abroad his policy was everywhere successful, and opened the way for the policy of Louis XIV. By means of an alliance with Crom well, he recovered the north-western cities of France, though at the price of yielding Dunkirk to the Protector. On the Baltic,
France guaranteed the Treaty of Oliva between her old allies Sweden, Poland and Brandenburg, which preserved her influence in that quarter. In Germany he, through Hugues de Lionne, formed the league of the Rhine, by which the states along the Rhine bound themselves under the headship of France to be on their guard against the house of Austria. By the Treaty of the Pyrenees Spain recovered Franche Comte, but ceded to France Roussillon, and much of French Flanders ; and what was of greater ultimate importance to Europe, Louis XIV. was to marry a Spanish princess. He died at Vincennes on March 9, 1661, leav ing a fortune estimated at from 18 to 4o million livres behind him, and his nieces married into the greatest families of France and Italy.
Mazarin was not a Frenchman, but a citizen of the world, and always paid most attention to foreign affairs; in his letters all that could teach a diplomatist is to be found, broad general views of policy, minute details carefully elaborated, keen insight into men's characters, cunning directions when to dissimulate or when to be frank. Italian though he was by birth, education and nature, France owed him a great debt for his skilful management during the early years of Louis XIV., and the king owed him yet more, for he had not only transmitted to him a nation at peace, but had educated for him his great servants Le Tellier, Lionne and Colbert. Literary men owed him also much; not only did he throw his famous library open to them, but he pensioned all their leaders, including Descartes, Vincent Voiture (1598-1648), Jean Louis Guez de Balzac (1597-1654) and Pierre Corneille.