Giovanni Panerai founded Officine Panerai in 1860 on Florence's Ponte alle Grazie as a watchmaker's shop and watch school. By the 1910s, under his grandson Guido Panerai, the firm had become the primary supplier of precision instruments and luminous materials to the Italian Royal Navy. Guido patented the Radiomir luminous compound (radium-based) in 1916, which provided significantly brighter underwater legibility than any competing material. The Italian Navy specified Panerai instruments for submarines, torpedo boats, and frogman equipment throughout the 1920s and 1930s.
The 1936 Radiomir watch was developed specifically for the Italian Navy's elite frogman combat divers (the Decima Flottiglia MAS), who used it during covert sabotage missions in Allied harbours during WWII. The original Radiomir used a Rolex-supplied Cortebert movement in a large 47mm cushion case with the patented Panerai luminous compound on the dial. After the war, Panerai developed the 1949 Luminor with a new tritium-based luminous material and a patented crown-protecting device that remains the signature Panerai case feature. Production remained exclusively military through the 1970s and 1980s.
In 1993 Panerai opened civilian sales for the first time, with a limited series that sold slowly initially. The decisive moment came in 1995 when Sylvester Stallone wore a Panerai Luminor in the film Daylight and subsequently commissioned personal editions, triggering a celebrity endorsement wave that included Arnold Schwarzenegger and Jason Statham. The 1997 Richemont acquisition provided capital for the transition from military-adjacent small-series production to large-scale luxury manufacture. Today Panerai operates a modern manufacture in Neuchâtel, Switzerland, producing in-house P.5000 and P.9000 series automatic calibres, while retaining the Florence heritage identity.
