A quarrel with a member of an illustrious French family, the chevalier de Rohan, resulted in Voltaire's second incarceration in the Bastille, from which he was released within two weeks on his promise to quit France and proceed to England. Accordingly he spent about two years in London. Voltaire soon mastered the English language, and in order to prepare the British public for an enlarged edition of his Poème de la ligue, he wrote in English two remarkable essays, one on epic poetry and the other on the history of civil wars in France. For a few years the Catholic, autocratic French government prevented the publication of the enlarged edition of Poème de la ligue, which was retitled La Henriade (The Henriad). The government finally allowed the poem to be published in 1728. This work, an eloquent defense of religious toleration, achieved an almost unprecedented success, not only in Voltaire's native France but throughout all of the continent of Europe as well. In 1728 Voltaire returned to France. During the next four years he resided in Paris and devoted most of his time to literary composition. The chief work of this period is the Lettres philosophiques (The Philosophical Letters, 1734). A covert attack upon the political and ecclesiastical institutions of France, this work brought Voltaire into conflict with the authorities, and he was once more forced to quit Paris. He found refuge at the Château de Cirey in the independent duchy of Lorraine. There he formed an intimate relationship with the aristocratic and learned Gabrielle Émilie Le Tonnelier de Breteuil, marquise du Châtelet, who exerted a strong intellectual influence upon him.
Voltaire's sojourn at Cirey in companionship with the marquise du Châtelet was a period of intense literary activity. In addition to an imposing number of plays, he wrote the Élements de la philosophie de Newton (Elements of the Philosophy of Newton), and produced novels, tales, satires, and light verses.
Voltaire's stay at Cirey was not without interruptions. He often traveled to Paris and to Versailles, where, through the influence of the marquise de Pompadour, the famous mistress of Louis XV, he became a court favourite. He was first appointed historiographer of France, and then a gentleman of the king's bedchamber; finally, in 1746, he was elected to the French Academy. His Poem de Fontenoy (1745), describing a battle won by the French over the English during the War of the Austrian Succession, and his Précis du siècle de Louis XV (Epitome of the Age of Louis XV), in addition to his dramas La princesses de Navarre and Le triomphe de Trajan, were the outcome of Voltaire's connection with the court of Louis XV.
Following the death of Madame du Châtelet in 1749, Voltaire finally accepted a long-standing invitation from Frederick II of Prussia to become a permanent resident at the Prussian court. He journeyed to Berlin in 1750 but did not remain there more than two years, because his acidulous wit clashed with the king's autocratic temper and led to frequent disputes. While at Berlin he completed his Siècle de Louis XIV, a historical study of the period of Louis XIV (1638-1715). For some years Voltaire led a migratory existence, but he finally settled in 1758 at Ferney, where he spent the remaining 20 years of his life. In the interval between his return from Berlin and his establishment at Ferney, he completed his most ambitious work, the Essai sur l'histoire générale et sur les moeurs et l'esprit des nations (Essay on General History and on the Customs and the Character of Nations, 1756). In this work, a study of human progress, Voltaire decries supernaturalism and denounces religion and the power of the clergy, although he makes evident his own belief in the existence of God.
After settling in Ferney, Voltaire wrote several philosophical poems, such as Le désastre de Lisbonne (The Lisbon Disaster, 1756); a number of satirical and philosophical novels, of which the most brilliant is Candide (1759); the tragedy Tancrède (1760); and the Dictionnaire philosophique (1764). Feeling secure in his sequestered retreat, he sent forth hundreds of short squibs and broadsides satirizing abuses that he desired to expose. Those who suffered persecution because of their beliefs found in Voltaire an eloquent and powerful defender. The flavor of Voltaire's activities could be summarized in the phrase he often used: écrasons l'infâme ("let us crush the infamous one"). With this phrase, he referred to any form of religion that persecutes no adherents or that constitutes fanaticism. For Christianity he would substitute deism, a purely rational religion. Candide, in which Voltaire analyzes the problem of evil in the world, depicts the woes heaped upon the world in the name of religion. He died in Paris, May 30, 1778.