Treaty of the Three Black Eagles

The Treaty of the Three Black Eagles (because all three signatories used a black eagle as a state symbol, in contrast to the white eagle, a symbol of Poland) or the Treaty of Berlin (where it was signed by Prussia), was a secret treaty between the Austrian Empire, the Russian Empire and Prussia. Signed between Russia and Austria on 13 September 1732 and joined by Prussia on 13 December that year, it concerned the joint policy of those three powers in regard to the succession of the Polish throne in light of the expected death of the Augustus II of Poland (of the Saxon House of Wettin) and the Polish custom of royal elections. The three powers agreed that they would oppose another candidate from the House of Wettin, as well as the candidacy of the pro-French Pole Stanisław Leszczyński, father-in-law of Louis XV. Instead, they chose to support either Infante Manuel, Count of Ourém, brother of the Portuguese king, or a member of the Piast family.

The Treaty of the Three Black Eagles had several goals. None of the three parties were serious about their support for the Portuguese count. The agreement had provisions for all three powers agreeing that it was in their best interest that their common neighbour, the Polish-Lithuanian Commonwealth, did not undertake any reforms that might strengthen it, and that its elected monarch should be friendly towards them. In addition to the obvious - increasing the influence of the three powers over the Commonwealth - Austria and Russia also wanted to damage the possibility of a French-Prussian-Saxon alliance. Prussia received promises of support for its interests in Courland (now southern and western Latvia).

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