Siena - Historic Centres Ghetto The Sienese Ghetto was the seat of all Jews who moved to Siena after the second half of the sixteenth century, from Cosimo I. The Jews had been part of the Sienese city since the twelfth century and saw their habits change going to settle in the alley of the Ghetto. In addition, they were forced to wear a yellow sign to stand out from Christians, and they also paid a collective tax.