A convention of the princes, dignitaries, and delegates of the German empire, for legislative or administrative purposes, of which the most important in a historical point of view are diets held at Augsburg in 1518, at Worms in 1521, at Nuremberg in 1523, 1524, at Spires in 1526, 1529, at Augsburg in 1530, at Cologne in 1530, at Worms in 1536, at Frankfort in 1539, at Ratisbon in 1541, at Spires in 1544, at Augsburg in 1547, 1548, 1550, and at Ratisbon in 1622.