Jacobsz. was deeply influenced by the Mannerist style of fellow Amsterdam painter Jan van Scorel. His painting The Crossbowmen (1529) was regarded as his most important piece, and was the first militia portrait in Dutch history.
Jacobsz. was influenced by the Mannerist style of Jan van Scorel, a fellow Amsterdam painter. His painting The Crossbowmen (1529) is considered his most important work and represents an early milestone in Dutch militia portraiture.