Rarely have a man and his hat been so linked in the collective imagination as Napoleon and his black, two-cornered hat.

Next month, a "bicorne" felt hat thought to have belonged to the French emperor will be up for auction in Fontainebleau in what the auctioneer calls the "sale of a century" for fans of the legendary leader.

Nearly 1,000 objects will be put on sale by auction house Osenat on Nov. 15 and 16, with the highlight being one of the iconic black hats said to have been worn by Napoleon during the Battle of Marengo in Italy in 1800.

"Napoleon and his hat is one and the same," auctioneer Jean-Pierre Osenat told Reuters TV. "There is no other object in France's history that is more symbolic of the person it represents."

His trademark look was not accidental, Osenat added.

In the early 19th century, such bicorne hats were worn with the corners pointing front and back, but Napoleon, "to make himself noticed", changed the angle, Osenat said, wearing his with the points facing the sides.

During the 15 years of the empire, Napoleon went through about 120 hats, usually supplied by the Poupart & Cie company, located in what is now known as the Palais-Royal in Paris, and costing about 60 francs.

"Napoleon always had 12 hats in use, each would last three years and were replaced at the rate of four per year," reads the catalog. "As he didn't like new hats, he had them broken in by Constant (his valet)."

About 20 to 30 of the hats are still in existence, most in the collection of museums.

Estimated at 300,000-400,000 euros ($379,900-$506,500), the hat to be auctioned is in excellent condition, still retaining its lining of gray-green silk.

The hat fell into possession of the head veterinary surgeon at the Imperial stables at the beginning of the 19th century. It was then sold at Paris' famous Drouot auction house in 1926 and acquired by the royal family of Monaco.

The great grandfather of Prince Albert of Monaco, head of the centuries-old House of Grimaldi, was a devoted Napoleonic collector. In the 1960s, the family created a museum, whose objects are now being auctioned to make room for one focusing on the family's history, Osenat said.

The auction also includes portraits of Napoleon, tricolour military sashes and medals, marble and bronze busts and statues of the emperor and other objects including Napoleon's gloves, razor and pocket watch.

The collection even includes a white shirt worn by Napoleon at Sainte-Helene, estimated at 30,000-40,000 euros, and a pair of his white silk stockings, estimated at 4-5,000 euros.

Despite the size and breadth of the collection, Osenat said for Napoleon admirers - and for auctioneers - "the absolute top is to have a hat".