Commonplace Fun Facts has documented a war fought over a pig, a war against emus, and another that was fought over spilled soup. None of this can quite compare to one of the bloodiest wars of the medieval age when over 2,000 lives were lost and the political structure of Italy was transformed — all over a bucket.

Our story begins in October 1154. Holy Roman Emperor Frederick Barbarossa took issue with the whole idea that the Pope having political authority over the Holy Roman Empire. To settle the matter, Frederick invaded Italy and seized control of the cities of Pavia, Milan, and Tortona. He proclaimed himself King of Italy before setting to work expanding his kingdom by conquering Bologna and Tuscany.

Thinking that he had sufficiently proven his point, Frederick went to Rome to speak with Pope Alexander III. The Pope was unwilling to abdicate his right to crown the Holy Roman Emperor. This was a practice dating back to 962 when Pope John XII crowned the first Holy Roman Emperor, Otto I (also known as Otto the Great). Alexander insisted that the right fell to him as God’s chosen representative on earth.

Frederick left Rome with a chip on his shoulder. He continued invading Italian cities until he was defeated by the pro-papal Lombard League at the Battle of Legnano on May 29, 1176. Frederick returned to Germany, leaving a decidedly-messy division of political loyalties in his wake.

Italy had yet to unify as a nation and existed as a number of allied city-states. Each of these city-states took sides in this conflict between the two powers. On one side were the pro-emperor Ghibellines. Opposing them were the pro-papal Guelfs. Modena was under Ghibelline control, while Bologna was Guelf.

With Modena and Bologna only 50 km (31 miles) apart, the tensions between the two ran high and occasionally resulted in violence. In 1296, for example, Bologna attacked and seized portions of Modena-controlled territory. The cities of Bazzano and Savigno fell under Guelf influence for a while until Modena regrouped and took the lands back, bringing the cities again under the influence of the Ghibellines. The border territories passed back and forth over the years in a never-ended series of raids and mini-invasions.

The violence escalated after Rinaldo “Passerino” Bonacolsi became the Ghibelline ruler of Mantua, Modena, Parma, and Reggio in 1309. Pope John XXIII declared him to be an enemy of the Church and offered spiritual incentives to anyone who successfully attacked Bonacolsi or his holdings.

By the start of 1325, the violence was nearly nonstop. In July of that year, raiding parties from Bologna went on a two-week killing and burning spree throughout Modenese farmland. Bonacolsi responded by sending troops to capture the Bolognese fort at Monteveglio.

In the midst of all of this bloodshed, it seems odd that the straw that broke the camel’s back was something we would chalk up to a college fraternity prank. One night some Modenese soldiers snuck into Bologna. Proceeding to the town’s well, the soldiers found a bucket filled with some goods that had been stolen from Modena in a raid. The soldiers grabbed the bucket and the contents and hurried back home.

The bucket (possibly a replica) that triggered the War of the Oaken Bucket, on display at Torre della Ghirlandina.

Representatives of Bologna demanded the return of the bucket and its loot. They insisted they had stolen it first, and so it should reside with them as a trophy of war. Modena didn’t see it the same way and refused to send the bucket back.

Up until this point, people had been killed, territory had been conquered and re-conquered. Skirmishes had been going on for nearly 150 years. The bucket, however, was more than either side could bear. Bologna declared open war against Modena. Modena reciprocated.

The War of the Oaken Bucket began on Friday, November 15, 1325. Malatestino dell Occhio, Lord of Rimini, led the Bolognese and their allies from Florence and Romagna to besiege Monteveglio.

Bonacolsi responded with troops from Modena, Mantua, and Ferrara, as well as German reinforcements, sent by the emperor. Altogether, he commanded about 5,000 foot soldiers and 2,000 mounted knights. Pope John XXIII countered with an army of 30,000 foot soldiers and 2,000 knights on horseback.

Despite their smaller numbers, the Modenese managed to route the larger Guelf force, which retreated back to Bologna. The Modenese decided against besieging the city. Instead, they destroyed the outer protective castles of Crespellano, Zola, Samoggia, Anzola, and Castelfranco. They captured 26 nobles and took them back to Modena as hostages.

The battle took the lives of 2,000 men. The official war ended a couple of months later with a treaty that returned Monteveglio and other properties to Bologna.

After the war, the oaken bucket was proudly displayed in Modena and kept in the Torre della Ghirlandina as a memorial of the city’s victory. The one on display today is probably a replica, but it remains a lasting reminder of a war that spilled far more blood than the bucket can hold.

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