Giacomo Coltrini (16th century) was an Italian painter, active mainly in a Renaissance style in Brescia, and a military engineer for Venetian Republic. He painted frescoes for the subterranean church of San Faustino Maggiore in Brescia. He died as a military engineer in Candia. Titian's paternal uncle, Gregorio Vecelli, lived in Coltrini's house in Venice.
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Giacomo Coltrini Wikipedia(Text) CC BY-SA