NAPOLEON I (Emperor of France, 1804-1821). Letter signed ('Napoleon') to the King of Prussia (Frederick William III), Paris, 'le cinq Pluviôse an treize (25 janvier 1805)', acknowledging his letter of 15 December 1804 announcing the birth of a prince and sending congratulations and assurances of good will, 'Ne doutez pas du plaisir avec lequel je saisis cette occasion pour renouveller à Votre Majesté les assurances de mon inviolable amitié', one page, folio, the letter written in a calligraphic hand, annotated in a different hand in German in the upper margin (integral leaf cut away, tiny splits in folds repaired with tape, and traces of paste on verso slightly discoloured).