with wording `To your Highness sovereign king and elector, dearest brother and friend.` Gdańsk, March 13, 1716 1 page. 35 x 23 cm. Handwritten signature of Catherine I. Catherine expresses her joy regarding `happy being delivered of a child by your Majesty`s spouse queen ` and thanks for `being appointed a Godmother of newborn Princess`. End signature: your royal majesty`s sister, friend and godmother Ekaterina`. Friedrich Wilhelm I (1688-1740) – the Second King of Prussia, Brandenburg Crown Prince (Elector) since 1713 from Hohenzollern dynasty. He founded Prussia as independent state in European policy and laid basis for its future transformation into a great empire under his son Friedrich II the Great. He met Tsar Peter I in 1716. Russian Tsar greatly impressed Friedrich Wilhelm I. Later both monarchs became allies and friends. On March 13, 1716 the 4th child daughter Filipina Charlotte was born in the family of the Prussian king Friedrich Wilhelm I and his spouse Sofia Dorothea of Hannover. Provenance: Sergey Lifar’s collection.