The remainder of Pereira's term of office passed in comparative tranquillity. He was succeeded in 1860 by another representative of his own party, Don Bernardo Berro, who was elected in constitutional fashion. Three years later, however, General Flores entered the arena of politics once more. The pretext under which hostilities broke out was slight enough in itself. A refusal on the part of the Government to permit the celebration of the anniversary of the Battle of Quinteros had enraged the Colorados, and Flores, espousing their cause, led an army into the field. A lengthy series of battles ensued, in the majority of which Flores was successful. While the war was still raging, Berro, having completed his term, was succeeded as President by Don Atanasio Aguirre. Flores, however, having now obtained the active support of Brazil, was carrying all before him, and in February of 1865 he entered Montevideo in triumph, and was proclaimed provisional Governor and then Dictator of the Republic. In recapitulating the history of Uruguay at this period the incessancy of the stream of warlike events is amazing. Scarcely had Flores seated himself upon what was virtually the throne of his dictatorship when an event of international importance, the Paraguayan war, occurred that was destined to convulse three republics and an empire. The pretext on which war was declared was the armed intervention of Brazil in the affairs of the Banda Oriental, and the support lent to Flores by the Brazilian army--an interference that Francisco Solano Lopez, the tyrannical Dictator of Paraguay, took upon himself to resent hotly. Yet, even had not this particular bone of contention come into being, the war was undoubtedly inevitable. Paraguay's distrust of Brazil, and the latter's dread of the really formidable military forces that the inland republic had gathered together, had piled up a situation that only the faintest flame was required to set ablaze. The military strength of Paraguay at this period was considerable. With an army of eighty thousand men of wild courage, backed by an adequate number of cannon, she might well have bidden defiance to any other single republic of South America. But her strength was exceeded by her confidence. Desirous of sweeping all before him, Lopez divided his forces, and dispatched an army to the north in order to invade Brazil, while another corps was told off to strike in a south-easterly direction. In order to effect this latter move it was necessary to obtain Argentina's consent to cross her province of Corrientes. This permission, which would have involved a breach of neutrality, was, not unnaturally, refused. Incensed at this check to his plans, Lopez declared war upon Argentina, and occupied the province of Argentina by force of arms. In the meanwhile Flores, in return for the support he had received from Brazil, threw in the lot of the Banda Oriental with that of the northern empire.