Answer: Declaration of Pillnitz, joint declaration issued on August 27, 1791, by Holy Roman Emperor Leopold II and King Frederick William II of Prussia, urging European powers to unite to restore the monarchy in France; French King Louis XVI had been reduced to a constitutional monarch during the French Revolution. The French government largely interpreted it as a threat to its sovereignty, and a series of provocations ensued, culminating in France declaring war on Austria (over which Leopold ruled) in April 1792.
The French Revolution was greeted with apprehension by many European leaders, who feared unrest in their own countries. Monarchs grew particularly worried as Louis XVI was forced to accept the authority of the newly proclaimed National Assembly in 1789. Unhappy as a constitutional monarch, he engaged in various duplicities, and in June 1791 he attempted to escape to Varennes but was subsequently captured. Two months later Leopold and Frederick William met in Pillnitz, Saxony (now in Dresden, Germany). Both were concerned about the possible spread of revolution, and they also faced strong pressure from French émigrés to intervene. Furthermore, Leopold was the brother of Louis’s wife, Marie Antoinette, whose safety was in doubt. These concerns led the two men to issue a five-sentence declaration that stated “that they view the situation in which the King of France currently finds himself as a subject of common interest for all of Europe’s sovereigns.” They continued by calling on these powers to “use the most efficient means…to place the King of France in a position to be totally free to consolidate the bases of a monarchical government.”