The most extensive non-judicial activity in which the audiencia participated at any time was its assumption of the provisional government of the colony during vacancies in the governorship. Aside from the ten different occasions on which this was done, the audiencia very frequently assumed control of the government when the exigencies of defense and foreign conquest rendered necessary the temporary absence of the governor. This was true at irregular intervals during the administrations of Governors Pedro Bravo de Acuña (1602-1606), Juan de Silva (1609-1616), Juan Niño de Tavora (1626-1632), Sebastián Hurtado de Corcuera (1635-1644) and Diego Fajardo (1644-1653). The administrations of these several governors were characterized by extensive military operations, largely in a foreign field, and the audiencia not only took over governmental affairs but it assumed the obligations of defense during their absence. On such occasions, of course, the tribunal retained its exercise of judicial functions. Since the audiencias in Perú and New Spain assumed the government much earlier than did the audiencia in the Philippines, and as the laws authorizing the rule of the audiencia were promulgated first to meet conditions in those viceroyalties, it seems advisable to inquire into the circumstances surrounding the establishment and development of this practice there. Having done this, we shall proceed to a study of the ad interim rule of the Audiencia of Manila, noting particularly the causes of the success or failure of its administration and the effect of this practice upon the subsequent relations of the audiencia and the governor. The first law in the Recopilación authorizing the assumption of the government by an audiencia was promulgated as early as March 19, 1550. This law provided that in case of a vacancy in the office of Viceroy of Perú, the audiencia there should succeed to the governments of Perú, Charcas, Quito and Tierra Firme, and that the three last-named subordinate audiencias should obey the mandates of the Audiencia of Lima until a permanent successor to the viceroy was named. [579] This law was proclaimed again on November 20, 1606.