On the Louvre's website, you can read about it's connection to Napoleon:
Through the treaties of Tolentino and Campo Formio, France acquired numerous paintings and antiquities from the Vatican and the Venetian republic. These were enriched by spoils from Napoleon I's conquests. The museum, of which Dominique-Vivant Denon had become director in 1802, was renamed the Musée Napoléon in 1803. A bust of the emperor by Bartolini was installed over the entrance. After the fall of the empire in 1815, each nation reclaimed its treasures and the museum was disbanded.
Wikipedia has a whole category for famous antiquities looted by Napoleon; some still remain in the Louvre. England also benefited: the Rosetta Stone was discovered by scholars imported by Napoeon in advance of his Egyptian campaign, and was subsequently "confiscated" by English gentlemen connoisseur scholars/soldiers. However, it was not just antiquities Napoleon had a taste for; he and his generals liked art, too, and because his siblings were installed as monarchs all over Europe, looted art became the nucleus for major European museums:
Many works confiscated from religious institutions under the French occupation now form the backbone of national museums: Napoleon's art-loot depots became the foundation of Venice's Accademia, Milan's Brera galleries. His brother Louis founded Amsterdam's Rijksmuseum; brother Joseph started Madrid's Prado" (for the Spanish royal collection).So Napoleon touched the histories of museums in Egypt, Italy, Spain, France, Germany, England, America, and even Russia. This is quite apart from the number of museums that now hold relics of his life and reign. Pretty impressive, I'd say - but is it as impressive as his physique?
Napoleonic commander and Marechal Nicolas Jean de Dieu Soult stole in 1810 six large pictures painted by Murillo in 1668 for the Hospital de la Caridad in Seville. One painting, The Return of the Prodigal Son, is now in the National Gallery of Art, Washington, a second looted painting, The Healing of the Paralytic, is in the National Gallery, in London, only two of the original paintings have returned to Seville.
Another French general looted several pictures, including four Claudes and Rembrandt's Descent from the Cross, from the Landgrave of Hesse-Kassel in 1806. The stolen goods were later bought by the Empress Josephine and subsequently by the tsar. Since 1918, when the Bolshevik government signed a peace treaty with Germany and Austria have German negotiators demanded the return of the paintings. Russia refused to return the stolen goods, the pictures still remain in the Hermitage. [source]
Bonaparte at the Bridge of the Arcole, by Baron Antoine-Jean Gros, (ca. 1801), Louvre, Paris
Napoleon Crossing the Alps [original version of 5], by Jacques-Louis David, 1801, Chateau de Malmaison