Possible Clues:

• 'Olympia' artist, 1863
• Painter, male and French
• His works mark the start of modern art
• 'La Musique aux Tuileries' painter
• Artist with long hair, beatnik at heart
• What the mnemonic 'Every good boy does fine' represents
• Artist mid-morning, maybe, returning
• Painter Édouard often confused with painter Claude
• Artist paid to pen article
• French painter returning mid-morning?