converts". After this, the Huguenots (with estimates ranging from 200,000 to 1,000,000) fled to Protestant countries: England, the Netherlands, Switzerland, Norway, Denmark, and Prussia—whose Calvinist Great Elector Frederick William welcomed them to help rebuild his war-ravaged and underpopulated country. Following this exodus, Huguenots remained in large numbers in only one region of France: the rugged Cévennes region in the south. There were also some Calvinists in the Alsace region, which then belonged to the Holy Roman Empire. In the early 18th century, a regional group known as the Camisards (who were Huguenots of the mountainous Massif Central region) rioted against the Catholic Church, burning churches and killing the clergy. It took French troops years to hunt down and destroy all the bands of Camisards, between 1702 and 1709. End of persecution By the 1760s Protestantism was no longer a favourite religion of the elite. By then, most Protestants were Cévennes peasants. It was still illegal, and, although the law was seldom enforced, it could be a threat or a nuisance to Protestants. Calvinists lived primarily in the Midi; about 200,000 Lutherans accompanied by some Calvinists lived in the newly acquired Alsace, where the 1648 Treaty of Westphalia effectively protected them. Persecution of Protestants diminished in France after 1724, finally ending with the Edict of Versailles, commonly called the Edict of Tolerance, signed by Louis XVI in 1787. Two years later, with the Declaration of the Rights of Man and Citizen of 1789, Protestants gained equal rights as citizens. Right of return to France in the 19th and 20th centuries The government encouraged descendants of exiles to return, offering them French citizenship in a 15 December 1790 law: All persons born in a foreign country and descending in any degree of a French man or woman expatriated for religious reason are declared French nationals () and will benefit from rights attached to that quality if they come back to France, establish their domicile there and take the civic oath. Article 4 of 26 June 1889 Nationality Law stated: "Descendants of families proscribed by the revocation of the Edict of Nantes will continue to benefit from the benefit of 15 December 1790 Law, but on the condition that a nominal decree should be issued for every petitioner. That decree will only produce its effects for the future." Foreign descendants of Huguenots lost the automatic right to French citizenship in 1945 (by force