Donativum (plural donativa) was the name given to the gifts of money dispersed to the soldiers of the Roman legions or to the Praetorian Guard by the Roman Emperors. The purpose of the donativa varied: some were expressions of gratitude for favors received, and others outright bribery for favors expected in return. Donativa were normally rendered at the beginning of each new emperor's reign. During the 2nd and 3rd centuries, this form of bribery became a crucial part of any successful ruler in Rome. Such was the case with many of the soldier-emperors from 235 to 248.