(b. 1624, Genova, d. 1659, Genova)
Painter and draughtsman, son of the painter Bernardo Castello and the nephew of Giovanni Battista Castello. He was one of the leading Ligurian painters of the 17th century, whose art developed from a continuous and passionate study of a wide range of sources. His paintings of mythological and religious subjects unite an elegant figure style with an interest in dramatic and violent compositions; his touch is spontaneous and his palette vibrant with reds and pinks, blues and yellows. His brilliant decorative frescoes introduced the splendour of the High Baroque to Genoese painters. He was well known for his rapid oil sketches, with light and lively brushwork, which anticipate aspects of the Rococo. His lively frescoes of glowing colour and dramatic illusionism in various Genoese palaces made him most famous. His style united elegant figures with dramatic, violent compositions composed of spontaneous brushwork and vibrant colours.
Few of his paintings are dated or datable, and his stylistic development remains highly controversial.