According to the legend, the church was commissioned by the Lombard Queen of Italy, Theodelinda. She had made a vow to build a church entitled to St. John, and when riding along the Lambro River, she was halted by a dove who told her Modo, Latin for "here", to which she replied Etiam ("yes") . Monza itself was initially known as Modoetia.
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The area of current Lombardy was settled at least since the 2nd millennium BC, as shown by the archaeological findings of ceramics, arrows, axes and carved stones... continues on wikipedia