Zelo Buon Persico

The name comes from Latin agellum, “little field”; the second half from one Gompertus, named in a twelfth-century document in the bishop's archive of Lodi as owner of land here. From agellum Gomperticum, Gomperto's holding, the form is thought to have slid to Gello, Zello, Zelo. The holding was named for its position: in Roman times it lay between two large estates, Agrum Martianum and Agrum Mutianum, today Marzano and Muzzano, the second now a hamlet here.

The arms are blue: a silver two-towered castle on a green field, a gold lion rampant above it. The castle is Bisnate's, the lion the land of Zelo, the green the fertility of the soil. Bisnate was its own comune, guarding a crossing of the Adda, fortified in the eleventh century, its castle built in the fifteenth; the merger became final in 1841, and Casolate, Mignete and Villa Pompeiana followed in 1869.