MISSI DOMINICI, the name given to the officials commissioned by the Frankish kings and emperors to supervise the administration of their dominions. Their institution dates from Charles Martel and Pippin the Short, who sent out officials to see their orders executed. When Pippin became king in 754 he sent out missi in a desultory fashion; but Charlemagne made them a regular part of his administration, and a capitulary issued about 802 gives a detailed account of their duties. They were to execute justice, to enforce respect for the royal rights, to control the administration of the counts, to receive the oath of allegiance, and to supervise the conduct and work of the clergy. They were to call together the officials of the district and explain to them their duties, and to remind the people of their civil and religious obligations. In short they were the direct representatives of the king or emperor. The inhabitants of the district they administered had to provide for their subsistence, and at times they led the host to battle. In addition special instructions were given to various missi, and many of these have been preserved. The districts placed under the missi, which it was their duty to visit four times a year, were called missatici or legationes. They were not permanent officials, but were generally selected from among persons at the court, and during the reign of Charlemagne personages of high standing undertook this work. They were sent out in twos, an ecclesiastic and a layman, and were generally complete strangers to the district which they administered. In addition there were extraordinary missi who represented the emperor on special occasions, and at times beyond the limits of his dominions. Even under the strong rule of Charlemagne it was difficult to find men to discharge these duties impartially, and after his death in 814 it became almost impossible. Under the emperor Louis I. the nobles interfered in the appointment of the missi, who, selected from the district in which their duties lay, were soon found watching their own interests rather than those of the central power. Their duties became merged in the ordinary work of the bishops and counts, and under the emperor Charles the Bald they took control of associations for the preservation of the peace. About the end of the 9th century they disappeared from France and Germany, and during the 10th century from Italy. It is possible that the itinerant justices of the English kings Henry I. and Henry II., the itinerant baillis of Philip Augustus king of France, or the royal enquêteurs of St Louis originated from this source.
See G. Waitz, Deutsche Verfassungsgeschichte (Kiel, 1844); E. Bourgeois, Le Capitulaire de Kiersy-sur-Oise (Paris, 1885); V. Krause, Geschichte des Institutes der missi dominici in the Mittheilungen des Instituts für österreichische Geschichtsforschung, Band XI. (Innsbruck, 1880). E. Dobbert, Über das Wesen und den Geschäftskreis der missi dominici (Heidelberg, 1861); N. D. Fustel de Coulanges, Histoire des institutions politiques de l’ancienne France (Paris, 1889–1890); L. Beauchet, Histoire de l’organization judiciaire en France, époque franque (Paris, 1865).