The diets of Augsburg were the meetings of the Imperial Diet of the Holy Roman Empire held in the German city of Augsburg. Both an Imperial City and the residence of the Augsburg prince-bishops, the town had hosted the Estates in many such sessions since the 10th century. In 1282, the diet of Augsburg assigned the control of Austria to the House of Habsburg. In the 16th century, twelve of thirty-five imperial diets were held in Augsburg, a result of the close financial relationship between the Augsburg-based banking families such as the Fugger and the reigning Habsburg emperors, particularly Maximilian I and his grandson Charles V. Nevertheless, the meetings of 1518, 1530, 1547/48 and 1555, during the Reformation and the ensuing religious war between the Catholic emperor and the Protestant Schmalkaldic League, are especially noteworthy. With the Peace of Augsburg, the cuius regio, eius religio principle let each prince decide the religion of his subjects and inhabitants who chose not to conform could leave.

The Imperial Diet was the deliberative body of the Holy Roman Empire. It was not a legislative body in the contemporary sense; its members envisioned it more like a central forum where it was more important to negotiate than to decide.