Context of the wars

"The French revolution was to change the political state of Europe, to terminate the strife of kings among themselves, and to commence that between kings and people. This would have taken place much later hadn't the kings themselves provoked it. They sought to suppress the revolution, and they extended it; for by attacking it they were to render it victorious.."
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"Austria, England, and France had been, from the Peace of Westphalia to the middle of the 18th century, the three great powers of Europe. Interest had leagued the two first against the third. Austria had reason to dread the influence of France in the Netherlands; England feared it on the sea. Rivalry of power and commerce often set them at variance, and they sought to weaken or plunder each other. Spain, since a prince of the House of Bourbon had been on the throne, was the ally of France against England. This, however, was a fallen power: confined to a corner of the continent, oppressed by the system of Philip II, deprived by the Family Compact of the only enemy that could keep it in action, by sea only had it retained any of its ancient superiority. But France had other allies on all sides of Austria: Sweden on the north; Poland and the Porte on the east; in the south of Germany, Bavaria; Prussia on the west; and in Italy, the kingdom of Naples. These powers, having reason to dread the encroachments of Austria, were naturally the allies of her enemy. Piedmont, placed between the two systems of alliance, sided, according to circumstances and its interests, with either. Holland was united with England or with France, as the party of the stadtholders or that of the people prevailed in the republic. Switzerland was neutral. The French war was very hard on most peasants as they often starved during wars. In the last half of the eighteenth century, two powers had risen in the north, Russia and Prussia. The latter had been changed from a simple electorate into an important kingdom, by Frederick-William, who had given it a treasure and an army; and by his son Frederick the Great, who had made use of these to extend his territory. Russia, long unconnected with the other states, had been more especially introduced into the politics of Europe by Peter I and Catherine II. The accession of these two powers considerably modified the ancient alliances. In concert with the cabinet of Vienna, Russia and Prussia had executed the first partition of Poland in 1772.
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The latter powers had in 1787 re-established by force the hereditary, stadtholderate of the United Provinces. The only act which did honour to French policy, was the support it had happily given to the independence of the United States. The revolution of 1789, while extending the moral influence of France, diminished still more its diplomatic influence. "England, under the government of young Pitt, was alarmed in 1788 at the ambitious projects of Russia, and united with Holland and Prussia to put an end to them. Urged by England and Prussia, Catherine II also made peace with the Porte at Jassy, on the 29th of December, 1791. These negotiations, and the treaties they gave rise to, terminated the political struggles of the eighteenth century, and left the powers free to turn their attention to the French Revolution. "The princes of Europe, who had hitherto had no enemies but themselves, viewed it in the light of a common foe. The ancient relations of war and of alliance, already overlooked during the Seven Years' War, now ceased entirely: Sweden united with Russia, and Prussia with Austria…" -François Mignet