The bubonic plague that swept Europe in 1630 was especially deadly in northern Italy. The city of Turin lost over 70 percent of its population. The neighboring city of Chieri appointed a commission to control the epidemic. In the absence of reliable medical solutions, the commission's first action was to seek divine help, vowing on June 26 to build a chapel to the Blessed Virgin of  Graces in Chieri's main church, Santa Maria della Scala (St. Mary of the Stair). Chieri lost 40 percent of its population. The survivors built the chapel, where a wooden statue of the Madonna and Child by Piedmontese sculptor Pietro Botto was installed in 1642. The Blessed Virgin of Graces became the patron saint of Chieri, which celebrates her with a novena of special masses and prayers and a secular program of music, dancing, and food, culminating in her festa on the second Monday in September.   

Sources:

 

"Cappella Municipale della Beata Vergine delle Grazie," Duomo di Chieri, www.duomodichieri.com 

"Festa Patronale," Comune di Chieri, www.comune.chieri.to.it

"Madonna delle Grazie scippata," Corriere di Chieri, 12-12-12, www.corrierechieri.it (picture)