The main interest of this investigation does not lie in the organization, the scope, nature, or detailed powers of the audiencia as an institution of the Philippines, but in its larger relation to the general field of Spanish colonial history and government. It applies to the entire field of Spanish colonial administration. It is related to the government of Perú, New Spain, Cuba, and other colonies wherein there were audiencias, and where functions similar to those of the Manila tribunal were exercised. The establishment of all these audiencias was part of the same movement, and the act of their creation was the product of experience gained in Spain through efforts at centralization there. The audiencias of the colonies were alike dependent on the Council of the Indies; common institutions and departments of government existed in Spain for the control and regulation of the tribunals of the colonies. All were of equal judicial rank before the Council of the Indies, and cases appealed to the latter from the several audiencias were treated in the same manner and considered as having equal rank and importance. The general powers and attributes of these audiencias were prescribed in the same code, the Recopilación, and general laws and cédulas of reform were expedited from time to time and sent to the tribunals of all the colonies. Such is the basis, therefore, of the claim that this is in reality a study of the audiencia as an institution, illustrated particularly by the history of that of the Philippines. A study of the audiencia of any colony is concerned with all of the problems that came up in its life--with legal, political, ecclesiastical, and social conditions. It will be seen that the audiencia was the one tribunal which regulated, checked, and often controlled both church and state in the colonies; it represented the king, and its duty was to see that the royal commands were obeyed; it was the royal audiencia. Isolated as were the officials of the Philippines, in those distant seas, removed from any but the most remote influence of the home government, beset on all sides by hostile forces, and dependent on themselves alone, conditions there present an especially favorable field wherein to note the ultimate possibilities of the authority of the audiencia. It is the design of this treatise to examine conditions in the Philippines under the aspects noted, and to assign them their place in the history of Spanish colonization. The investigation of what was, beyond doubt, the most important and many-sided institution in the Spanish administration of the Philippines provides a means of approach to that larger field of study.