Before he attacked and seized the crown of England in 1066, William the Conqueror held the title of Duke of Normandy, a region of northern France. Throughout the rest of his reign, and of the six English kings that followed, Normandy, while technically still owing its allegiance to France, operated under English control. More than a century later, King Richard I, known as the 'Lion-Heart', built a series of castles, including the imposing Château Gaillard, in order to retain his control of Normandy.

Built in the unusually short span of only one year, the full-sized Château Gaillard perched atop a triangular outcropping of rock overlooking the Seine River Valley northwest of Paris. Cliffs on three sides looking over a river provided the position with a formidable natural defense, limiting entrance to the site to a sloping plateau to the south. King Richard, a gifted engineer, instructed his workers to build a tower, called the 'inner bailey', roughly the shape of a human ear on the very edge of the cliff, which was then surrounded by a moat spanned by only one small natural bridge. Around the moat was a second wall, the 'middle bailey', itself ringed with towers and also breached by only a single gate. Finally, the 'outer bailey', a third walled courtyard, laid beyond the middle bailey gate, again ringed with towers. Although it cost Richard a fortune, the castle appeared impregnable.

Richard built fanatically, often joining the workmen personally. He referred to the castle as 'his daughter', and completed its construction in 1198. Only a few months later, Richard died after being shot by a crossbow during the siege of Chalus-Chabrol. He was succeeded to the throne by his brother John, whose religious demeanor led to the construction of a hastily-built chapel within the middle bailey, and whose relative lack of experience concerning architecture and warfare explained his subsequent order to construct a garderobe, or castle latrine, adjacent to the chapel, which required a sizable opening cut in the middle bailey's wall.

King Philip II of France took advantage of King John's relative inexperience in military matters. Philip, supporting Richard and John's nephew Arthur's claim to the English throne, began a campaign to retake Normandy, and French forces laid siege to the crucial Château Gaillard in September 1203. The French army approached from the only feasible direction, the south, digging trenches and building walls of its own for protection. A daring nighttime relief mission from King John's forces failed miserably, as the foot troops arrived before the ships did, allowing the French to dismantle each element in turn. By February 1204, King Philip's forces had managed to dig a tunnel under the outer bailey wall and collapse it, causing a breach through which their forces stormed. With this done, they were still faced with a problem: the middle bailey was reachable only by a drawbridge, which the English kept raised.

The French siege, and the conquest of Normandy itself, would have likely come to a screeching halt, were it not for a foot soldier from Gascony named Snubby Bogis. Snubby was creeping around the base of the middle bailey, not far from the steep cliff over the river, when he spotted the opening to the garderobe about three or four meters above ground. Realizing its implications, he got four of his companions to lift him up into the convenient hole in the wall. Emerging from the toilet, he dropped a rope and his friends climbed up after him. They crossed from the garderobe to the chapel, and found that it was locked from the outside. Thinking quickly, the five men banged on the door with their swords so hard that the English defenders thought the middle bailey had been broken and the whole army was upon them; they quickly set fire to the buildings and retreated to the inner bailey. Snubby and his friends then ran through the fire, opened the gates, and dropped the drawbridge, allowing the entire French force easy access.

The inner bailey was undermined shortly thereafter, as the natural bridge provided cover from the miners working in the moat. Château Gaillard fell to the French on March 8, and most of Normandy itself was back in undeniably French hands for the first time in almost 150 years, all due to an unguarded toilet.

Links and Sources:
"The Château Gaillard", by Thomas A. Janvier, from Harper's Magazine, volume 109, 1904.
Mediæval Military Architecture in England, Volume 1, by George Thomas Clark, Wyman and Sons, 1884.
Fighting Techniques of the Medieval World, AD 500 - AD 1500, by Matthew Bennett et. al., by Thomas Dunne Books, an imprint of St. Martin's Press, 2006
Painting of Château Gaillard by Dominique Pitte for the Les Andelys Municipal Tourism Office.