Art by Ambrogio Lorenzetti

Lorenzetti painted one of the most important secular works of the entire early Renaissance: The Allegory of Good and Bad Government (1338-39), a sprawling fresco cycle covering the walls of Siena's Palazzo Pubblico, the city's town hall, showing in exacting detail what a well-run city looks like versus a city ruled by tyranny. His "Bad Government" side contains the first known depiction of an hourglass in Western art. Vasari later wrote that Lorenzetti carried himself more like a gentleman-philosopher than a typical painter. He and his brother Pietro, also a painter, both died in the Black Death of 1348; Ambrogio's will is dated just weeks before his death.