So-called portrait of <a href="https://en.wikipedia.org/wiki/en:Catherine_the_Great" class="extiw" title="w:en:Catherine the Great"><span title="Empress of Russia (1729-1796)">Catherine II of Russia</span></a> (1729-1796), but it's probably a portrait of <a href="https://en.wikipedia.org/wiki/en:Duchess_Maria_Antonia_of_Bavaria" class="extiw" title="w:en:Duchess Maria Antonia of Bavaria"><span title="German composer, opera singer and librettist (1724-1780)">Maria Antonia Walpurgis of Bavaria</span></a> (1724-1780) with  the <a href="https://en.wikipedia.org/wiki/en:Order_of_Saint_Catherine" class="extiw" title="w:en:Order of Saint Catherine"><span title="order of knighthood for women in Russia">Order of Saint Catherine</span></a>.
<bdi>Circle of <a href="https://en.wikipedia.org/wiki/en:Jean-Marc_Nattier" class="extiw" title="w:en:Jean-Marc Nattier"><span title="French painter (1685-1766)">Jean-Marc Nattier</span></a>
</bdi>
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