Austria. The Peace of Teschen, signed on 13 May 1779, ended the brief conflict, with the queen imposing French mediation at her mother's insistence and Austria's gaining a territory of at least 100,000 inhabitants—a strong retreat from the early French position which was hostile towards Austria. This gave the impression, partially justified, that the queen had sided with Austria against France. Meanwhile, the queen began to institute changes in court customs. Some of them met with the disapproval of the older generation, such as the abandonment of heavy make-up and the popular wide-hooped panniers. The new fashion called for a simpler feminine look, typified first by the rustic robe à la polonaise style and later by the gaulle, a layered muslin dress Marie Antoinette wore in a 1783 Vigée-Le Brun portrait. In 1780 she began to participate in amateur plays and musicals in a theatre built for her by Richard Mique at the Petit Trianon. Repayment of the French debt remained a difficult problem, further exacerbated by Vergennes and also by Marie Antoinette's prodding Louis XVI to involve France in Great Britain's war with its North American colonies. The primary motive for the queen's involvement in political affairs in this period may arguably have had more to do with court factionalism than any true interest on her part in politics themselves, but she played an important role in aiding the American Revolution by securing Austrian and Russian support for France, which resulted in the establishment of the First League of Armed Neutrality that stopped Britain's attack, and by weighing in decisively for the nomination of Philippe Henri, Marquis de Ségur as Minister of War and Charles Eugène Gabriel de La Croix as Secretary of the Navy in 1780, who helped George Washington defeat the British in the American Revolutionary War, which ended in 1783. In 1783 the queen played a decisive role in the nomination of Charles Alexandre de Calonne, a close friend of the Polignacs, as Controller-General of Finances, and of the Baron de Breteuil as the Minister of the Royal Household, making him perhaps the strongest and most conservative minister of the reign. The result of these two nominations was that Marie Antoinette's influence became paramount in government, and the new ministers rejected any major change to the structure of the old regime. More than that, the decree by de Ségur, the minister of war, requiring four quarterings