There are testimonies of the presence of humans in the area of Monza in the Bronze Age (2000 years B.C.), but its history as a town starts in the Roman era when it was called 'Modicia'. After the fall of Rome, during the reign of the Ostrogoth Theodoric in the 5th century A.D., Monza became the see of the royal palace.
However, the city's importance rose in the late 6th and early 7th century with the government of the Longobardi. Teodolinda, married to Agilulfo king of Italy, decided to move their summer residence to Monza where she built a royal palace as well as an oratory near the castle dedicated to John the Baptist in the year 595.
The town would rise to the status of capital once again in the 10th century with king Berengario, who built a fortified area and granted Monza a certain degree of independence with its own system of weights and measures. He also donated large quantities of artworks to the cathedral.
After a period of changes in the relationship between Monza and Milan in the Middle Ages, a city to which Monza has been continuously subjected and independent throughout history, it fell into the hands of the Spanish crown. Spain's dominance over Monza ended in the 18th century when it was assigned to the Austrian Habsburg house, before being conquered by Napoleonic troops.
During the 19th century, when the Italian independence wars and the unification were underway, Monza became an important industrial capital dedicated to the manufacturing of silk and cotton textile. In 1900, the city witnessed the assassination of King Umberto I at the hands of Gaetano Bresci, an anarchist who shot the monarch four times on July 29 when he was visiting Monza. A monument, the Cappella Espiatoria, has been erected in the exact spot the king was murdered.
Monza suffered under the First and Second World Wars like most of Italy. At the beginning of the 21st century, the city had 120,000 inhabitants, and in 2009 it became the capital of the newly formed province of Monza and Brianza.