Napoleon Bonaparte's account of his stunning victory at the Battle of Austerlitz, which he dictated in exile on the island of Saint Helena, goes up for sale in Paris later this month.
The 74-page manuscript, dictated to his loyal aide-de-camp General Henri-Gatien Bertrand, contains several corrections made by the exiled emperor, who crossed out words and added remarks in the margins in tiny writing.
Napoleon's account of the 1805 "three emperors" clash with Russo-Austrian forces, which is considered his greatest military victory, takes readers through preparations for battle, the fighting itself and is completed by a battle plan drawn by Bertrand on tracing paper.
Napoleon does not refer to himself in the first person, opting instead to preface his remarks with "the emperor says".
The auction comes at the start of a year marking the bicentenary of Napoleon's death.
The manuscript comes with a guide price of one million euros and will be exhibited January 27-30 at the Paris gallery Arts et autographes.
Gallery owner Jean-Emmanuel Raux, a collector of French imperial memorabilia, found the manuscript in a trove of documents belonging to Bertrand's heirs.
"It's the most fabulous document about French history that you could find in a private collection," he said.
His daughter Alizee, who studied the manuscript in detail, said it was an "embellished account of the battle".
Within around nine hours on December 2, 1805, some 75,000 soldiers of Napoleon's Grande Armee outmanoeuvred a larger Russian-Austrian force at Austerlitz, in what was then the Austrian empire.
Napoleon details all the tactics deployed to try to dupe his opponents into believing that French forces were weak.
His exalted account trumpets the heroism of the French, from trooper to offier, and claims even wounded soldiers hailed the emperor.
The sale is part of the 'BRAFA in the Galleries' art fair taking place in 126 galleries in 13 countries from January 27 to 31.
Collectors can arrange to view the manuscript in person or over the internet.