Complex sentence: Born in Monza in the 14th century, he was an important member of the Ghibelline family of Monza, Bonincontro took an active part in the political struggles of his time, siding with the party of the Visconti, Dukes of Milan.
Split into simpler sentences: Born in Monza in or shortly before the 14th century, he was a member of an important Ghibelline family of that city. He took an active part in the political struggles of his time, siding with the party of the Visconti, Dukes of Milan.