The article aims at giving a general view of the legal regulation of the lakes of Insubria in the
Modern Age (16th-18th centuries). The lakes (Verbano/ Maggiore, Como, Varese, Ceresio, Mezzola)
were controlled by the Milanese government under the Spanish and Austrian rules, and later also in
part by Switzerland and by the King of Sardinia. The magistracy in charge, fishing rights and fish
trade regulations are investigated in the light of documents preserved mainly in the State Archives
of Milan and Como, and in the archive of the Borromeo family at Isola Bella.