The 1640 work, The Triumph of David by Ottavio Vannini, was hanging in the museum’s Early European Gallery, where the incident happened on Wednesday afternoon, said David Gordon, museum chief executive and director.
He said he was confident the museum could repair “serious” damage to the €220,000 painting.
The work depicts the end of the biblical tale of David and Goliath, with three maidens playing musical instruments and greeting David, who carries the severed head of giant Goliath.
A 21-year-old man from the town of Pewaukee wandered through the galleries for hours before taking off his shirt to reveal tattoos — Chinese symbols of faith, love, hope and peace — and attacked the painting, Gordon said.
“(He) claims that he was disturbed by the image of the head of Goliath and started kicking it and then he grabbed the painting,” he said. “He ripped it from the wall and carried on kicking. It happened very quickly.”
A staff member rushed in, and a security guard was there seconds later, Gordon said. Eventually, the man stopped kicking.
“He simply lay down on the ground on his stomach and said nothing,” he said.
The man had previously received psychiatric treatment and had been on medication, Gordon said. Police took him to jail.
The painting will be examined by conservators, and the museum’s insurance company would cover the repairs, Gordon said.
The painting was on loan since December from the Haukohl Family Collection, the largest collection of 17th-century Florentine art in the US. It is owned by Mark Fehrs Haukohl, a Milwaukee native and collector who lives in Houston.