Cartier was founded in 1847 when Louis-François Cartier, then an apprentice to Parisian jeweler Adolphe Picard, took over the business when his master passed away. By 1853, young Louis-François had become a favorite of Napoleon III’s cousin Princess Mathilde, who helped Cartier gain entry to Parisian society. For the next quarter century, Cartier was strictly a jeweler, but in 1874, Louis-François’s son Alfred gained the company’s reins. He in turn brought his sons, Louis, Pierre, and Jacques, into the firm—it was this third generation of Cartiers that would make the Paris jeweler’s name synonymous with luxury wristwatches. The first Cartier wristwatches were diamond-studded bracelets for ladies, which were introduced in 1888 and languished until Parisian fashions changed enough in the mid-1890s to encourage the adornment of a bare wrist with a watch. But the real wristwatch breakthrough came in 1904, when, according to Cartier lore, a Brazilian aviation pioneer named Alberto Santos-Dumont complained to his friend Louis Cartier of the shortcomings of fumbling with a pocket watch on a short test flight. Cartier made his friend a flat, square wristwatch called, appropriately, the Santos. In the process, Cartier popularized wristwatches in France and throughout the world. In 1912, Cartier introduced the oval Baignoire and tortoise-shell shaped Tortue models, followed by its most famous early wristwatch, the Tank, which was produced as a prototype in 1917 before being offered to the public in 1919. Reportedly inspired by the design of Renault tanks used during World War I, the Tank had legions of famous fans, including Rudolph Valentino, who wore a Tank in the 1921 silent classic "The Sheik." In the early 1920s, Cartier partnered with fellow Frenchmen Jaeger and Breguet to produce movements for its watches. Other illustrious Cartier collaborators included Swiss makers Vacheron Constantin, Patek Phillipe, and Audemars Piguet. During the 1920s, Cartier started stamping its watches with four-digit reference numbers—today, knowledgeable collectors know to look for and verify these codes before purchasing an antique Cartier wristwatch. That way, they can tell for certain if the 1932 waterproof Pasha (made for the Pasha of Marrakesh) that they are about to purchase is real or a fake. By 1940, Cartier had introduced a motoring watch, with a curved shape that was designed to be worn on the inside of the wrist—the winder was on the back of the watch, against the wearer’s skin, rather than the side. And then, in 1942, after the death of Louis Cartier, the company began several decades of stagnation. Countless variations of the Tank appeared (in the Chinoise, horizontal bars at the top and bottom of the dial rest on the Tank’s vertical "treads"), and in 1965 there was even a watch whose body was shaped like a parallelogram. But it was not until the Must de Cartier in 1976 and the reissue of the Santos in 1978 that the firm was able to reestablish itself as a player on the wristwatch scene.