The political history of 18th-century Europe begins in 1715 with the death of Louis XIV and ends in 1815 with the defeat of Napoleon. These years span the time between the Treaty of Utrecht and the Treaty of Vienna. At either end of the century, an attempt by the leading power to dominate the continent is frustrated by events in mid-century that cause the French Revolution (1789–1799), the defining event of the 18th century, and its aftermath.
The face of Europe in 1715 was formed by the Treaty of Utrecht, which served to end the War of the Spanish Succession in 1713. While France was defeated in this war, she made out well in the treaty, having kept her 1697 borders. This meant that France kept the earliest acquisitions of Louis XIV: Artois, the majority of Flanders, Valenciennes, Cambrai, Alsace and Franche Comté, in addition to Cerdagne and Roussilon, located along the borders of Spain.
The kingdom of France was larger than it had been 50 years earlier and covered a denser territory that made good strategic sense. France held important colonies in the West Indies and in North America and was still a major player in Europe and overseas. However, these successes had cost dearly, placing a strain on a system of government that was out of touch with the times.
France was still important among the nations of Europe, but that importance had declined. In Eastern Europe, two nations, Prussia and Russia, were growing more powerful, while to the west, Britain had gained the upper hand against France in terms of commercial wealth and colonial treasure. The Revolution of 1789 helped revive France as a power by giving her a new government and a new perspective on nationalism.
France was in a state of continuous warfare from 1792–1814. French rule stretched over large swaths of the continent, but these gains evaporated with the defeat of Napoleon at Waterloo in 1815. France never again ruled or strove to rule the continent.
Spain had been the strongest European power a century earlier, but after fighting three wars, her power had waned. The great powers fought about who would succeed Spain. Philip V, of the Bourbon family, ascended the Spanish throne in 1700, restoring some former glory to the proud country, but the alliance meant that Spain was now beholden and bound to France.
The alliance with the Bourbons replaced that of Spain with the Austrian Habsburgs. The Habsburgs were still land-wealthy, possessing Upper and Lower Austria, Styria, Carinthia, Carniola, Tyrol, Breisgau, Burgau, Bohemia, Moravia, Silesia, Hungary, Croatia and Transylvania. The Treaty of Utrecht added the Netherlands, Naples, Sardinia and Milan. The totality of these land possessions meant that the Habsburg Empire was at least the equal of France and Britain among European powers.
The Habsburgs also held the office of Holy Roman Emperor, an elective position. The position made the successors the inheritors of the ancient Roman Empire. However, the ridiculousness of this idea was expressed by Voltaire in 1756: "This agglomeration which was called and which still calls itself the Holy Roman Empire was neither holy, nor Roman, nor an empire." Napoleon forced Francis II to give up the empty title of Holy Roman Emporer in 1806.
Estimating the population of Europe during the 18th century is difficult and can only be based upon conjecture. Prior to 1800, no reliable population figures exist with the exception of those for Sweden and Finland, which had both set into motion a system whereby the people registered with their local parishes. Parish registration in these two countries was instituted from 1750.
In England, the Bill for Registering the Number of the People was introduced to Parliament in 1753. However, there was violent opposition to the idea of counting people. While the bill passed in the House of Commons, it was rejected in the House of Lords. Even those sources which should have provided a picture of the size of the population at that time, such as taxation records, are woefully inadequate and cannot be used as reliable measures. In 1788, for example, tax-collectors in Ireland had left out 200,000 households in counting the returns for the island's hearth tax. Census-taking did not begin in England or France until the early 19th century, and even then, it took some time to hone census-taking methods.
From 1750–1815, Christianity suffered a decline in comparison to the golden time of the Reformation and Counter-Reformation. Both the Protestant denominations and the Roman Catholic Church were in a state of weakness and decay. At the same time, it became popular in the more upwardly mobile classes of Western Europe to profess atheism and anticlericalism.