Eleven years after the first flight, the balloon was already a weapon. Between 1794 and 1945 it watched battlefields, carried a government over enemy lines, ran the world's first airmail at scale and, in its last military act, drifted bombs across an ocean on the jet stream. This page follows the balloon to war, from Fleurus to Oregon.
A balloon above the battle
On 26 June 1794, at the Battle of Fleurus in what is now Belgium, French officers rose in the tethered hydrogen balloon l'Entreprenant and spent hours above the field, reading enemy troop movements and sending reports down the cable. It was the first time an observation balloon worked over a battle, and the French won it. The Aerostatic Corps that flew l'Entreprenant is arguably the first air arm in history. It was disbanded within a decade, but the lesson survived it: from that day on, the high ground extended upward.
Telegrams from the sky
The idea returned wherever armies stalled. During the American Civil War the scientist-showman Thaddeus Lowe persuaded Abraham Lincoln to back a Union Army Balloon Corps, and in June 1861 he telegraphed the president directly from his balloon above Washington, describing the view from 500 feet. For the next two years Union gunners corrected artillery fire onto targets they could not see, guided by a man in a wicker basket with a telegraph wire running down the tether.
The airline out of a dying city
The strangest chapter came in 1870, when the Prussian army surrounded Paris and cut every road, rail line and telegraph wire. The city's answer was to become, for four months, the world's first airmail hub. About 66 balloons left Paris carrying roughly 102 passengers, some 400 homing pigeons and around 2.5 million letters. The great railway stations, their trains going nowhere, turned into balloon factories: envelopes were sewn and varnished in the halls of the Gare du Nord and the Gare d'Orleans, and sailors were recruited as pilots because they alone were at home with rigging and heights. Replies came back the only way they could, as microphotographed dispatches carried into the city by pigeon, then projected and copied out by clerks. It was airmail at scale a century before the airlines.
Gambetta flies over the enemy
On 7 October 1870 Leon Gambetta, the minister of the interior, climbed into the balloon Armand-Barbes on the heights of Montmartre and floated over the Prussian lines, under rifle fire, to organize the war from the provinces. A minister escaping a besieged capital by air became one of the defining images of the century, painted and reprinted ever since. Not every flight obeyed. On 24 November the Ville d'Orleans caught the wrong wind, crossed the North Sea by night and came down in Norway, roughly 1,400 kilometres from Paris. Its two-man crew survived, and the mail eventually reached its addresses. The wind chooses; that part has never changed.
The grim twentieth century
In the First World War, tethered kite balloons hung over every front directing artillery. Their observers were the first aviators routinely issued parachutes, because balloon-busting aces hunted them with incendiary ammunition. In the Second World War the balloon went on the defensive: barrage balloons floated over London and other cities, their steel cables forcing bombers higher and spoiling their aim. Then came the strangest weapon of the war. From November 1944 to April 1945 Japan released about 9,300 Fu-Go fire balloons into the newly discovered jet stream, paper spheres built to ride the wind to North America with incendiary and explosive charges. A few hundred arrived. On 5 May 1945 a picnicking group found one in the woods near Bly, Oregon; the explosion killed Elsie Mitchell and five children, the only deaths by enemy action on the US mainland in the entire war. The same jet stream now carries record chasers instead, a story we tell among the records and great adventures.
The wind still decides
Every story on this page turned on the weather, and modern flying still does, minus the rifles. Calm dawn air is the reason balloons launch at first light.
Balloons at war FAQ
When was a balloon first used in battle?
On 26 June 1794 at the Battle of Fleurus, where French officers observed enemy movements from the tethered hydrogen balloon l'Entreprenant and reported down the cable. France won the battle.
How did mail get out of Paris during the siege of 1870?
By balloon. About 66 balloons left the surrounded city between September 1870 and January 1871, carrying roughly 102 passengers and around 2.5 million letters. Replies returned as microfilmed dispatches flown in by homing pigeon.
What were Japan's Fu-Go balloon bombs?
Paper hydrogen balloons launched into the jet stream between November 1944 and April 1945, about 9,300 in all, designed to drop incendiaries on North America. One killed six civilians near Bly, Oregon on 5 May 1945, the only enemy-action deaths on the US mainland in the Second World War.
What did barrage balloons actually do?
They lifted steel cables over cities, ports and invasion fleets so that attacking aircraft had to fly higher and bomb less accurately, or risk shearing off a wing. Thousands flew over Britain during the Second World War.