Richelieu returned to power for a short interval, from 1820 to 1821. The press was more strongly censored, detention without trial was reintroduced, and "Doctrinaire" leaders, such as François Guizot, were banned from teaching at the École Normale Supérieure. Under Richelieu, the franchise was changed to give the wealthiest electors a double vote, in time for the November 1820 election. After a resounding victory, a new Ultra ministry was formed, headed by Jean-Baptiste de Villèle, a leading Ultra who served for six years. The ultras found themselves back in power in favourable circumstances: Berry's wife, the duchesse de Berry, gave birth to a "miracle child", Henri, seven months after the duc's death; Napoleon died on Saint Helena in 1821, and his son, the duc de Reichstadt, remained interned in Austrian hands. Literary figures, most notably Chateaubriand, but also Hugo, Lamartine, Vigny, and Nodier, rallied to the ultras' cause. Both Hugo and Lamartine later became republicans, whilst Nodier was formerly. Soon, however, Villèle proved himself to be nearly as cautious as his master, and, so long as Louis lived, overtly reactionary policies were kept to a minimum.