The Siege of Paris (September 19, 1870 - January 28, 1871) and the consequent capture of the city by Prussian forces, led to French defeat in the Franco-Prussian War. Balloon mail was the only means by which communications from the besieged city could reach the rest of France. The use of balloons to carry mail was first proposed by the photographer and balloonist Felix Nadar to perform tethered ascents for observation purposes. However the Prussian encirclement of the city made this pointless. Around 66 balloon flights were made, including one that accidentally set a world distance record by ending up in Norway. The vast majority succeeded: only five were captured by the Prussians, and three went missing, presumably coming down in the Atlantic or Irish Sea. The number of letters carried has been estimated at around 2.5 million. Some balloons also carried passengers, most notably L矇on Gambetta, the minister for War, who was flown out of Paris.