The Affair of the Sausages (1522) was the event that sparked the Reformation in Zürich. Huldrych Zwingli, pastor of Grossmünster in Zurich, Switzerland, spearheaded the event by publicly speaking in favor of eating sausage during the Lenten fast. Zwingli defended this action in a sermon called Von Erkiesen und Freiheit der Speisen, in which he argued, from the basis of Martin Luther's doctrine of sola scriptura, that "Christians are free to fast or not to fast because the Bible does not prohibit the eating of meat during Lent."

The Reformation in Zürich was promoted initially by Huldrych Zwingli, who gained the support of the magistrates of the city of Zürich and the princess abbess Katharina von Zimmern of the Fraumünster Abbey, and the population of the city of Zürich and agriculture-oriented population of the present Canton of Zürich in the early 1520s. It led to significant changes in civil life and state matters in Zürich and spread to several other cantons of the Old Swiss Confederacy, and thus initiated the Reformation in Switzerland.