Seveso (in Lombard language: Séves) is an Italian town and comune of 19,872 inhabitants situated in the Province of Milan, in the Region of Lombardy. The economy of the town has traditionally been based around the furniture industry.
Its name comes from the river of the same name which crosses the commune in a north-south direction.
Seveso lies on the national trunk road Statale dei Giovi, which connects Milan to Como and on the Milan-Meda motorway. It is also serviced by the Milan–Asso railway line.
In 1252 the church of Saint Peter Martyr (S. Pietro Martire) was constructed in homage to the Dominican order brother who had been assassinated in Seveso. The Church of the Seminary preserves in its crypt the knife which was used to kill him.
The town was struck in the 16th century by two episodes of famine and plague. During the 17th century, the town was ruled by several families, of which the Arese family left a number of outstanding monuments.
In 1798, Prince Giuseppe II of the Napoleonic Cisalpine Republic ordered the Dominicans to leave the monastery and church of Saint Peter. In the unification of the Kingdom of Italy, territory from Barlassina was passed to Seveso. This decision was rejected by the population and the two comuni were again separated in 1901.
Seveso made world headlines when, on July 10, 1976, storage vessels at the ICMESA chemical plant ruptured, releasing several kilograms of the dioxin TCDD (2,3,7,8-tetrachlorodibenzo-p-dioxin) into the atmosphere. Tens of thousands of farm animals and pets died or were later deliberately slaughtered, though it is believed that there was not a single human death directly attributable to the incident. The event came later to be known as the Seveso disaster. Nowadays in the main contaminated area there is a park called "Bosco delle Querce" (Wood of Oaks).