• Was an Italian Baroque painter.
• De Ferrari was born in Porto Maurizio.
• He came to Genoa to study law but instead became a painter.
• He apprenticed with Domenico Fiasella.
• He travelled to Parma (staying from 1669 to 1673), where he worked in quadratura frescoes.
• He ultimately joined his father-in-law, Domenico Piola, in the prolific studio known as Casa Piola, which was founded in the 1660s.
• In 1674, he painted the Glory of St Gaestano in a vault in the church of San Siro.
• During the 1680s Gregorio joined Andrea Seghizzi, who worked as quadraturista, to fresco several ceilings in the Palazzo Balbi-Senarega.
• During the Bombardment of Genoa, he frescoed an Allegory of Time and sculpted a frieze in the drawing room of the Villa Gropallo.
• Circa 1690, Gregorio frescoed a large vault in the Santi Giacomo e Filippo with an Assumption of the Virgin.
• In his later years he turned to modeling and colouring paper papier-mâché and plaster figures.
• Among the children of Gregorio and his wife, Margherita Piola, was the painter Lorenzo de' Ferrari, as well as his lesser-known brother, an art restorer named Giuseppe.
