diplomatic authorities residing in Montevideo that the Brazilian Imperial Government had determined the occupation of the Uruguayan territory to the north of the Rio Negro, in the form of reprisal, until they obtained guarantees and satisfactions from the government of the Uruguay. At all times his decisions were in accordance with the guidelines set out in the letter dated months ago, even though the conflict was already underway and diplomatic measures, in addition to failing, caused discontent in the Court. The situation of the Eastern Republic of Uruguay would generate by geopolitical aggravations what we know as the Paraguayan War, and Tamandaré's action in command of the Brazilian intervention was effective, acting with the necessary violence, in a timely manner and fulfilled its mission, using the means military personnel who were at his disposal. His initial participation in the conflict was of extreme importance for the provision of Brazilian forces, especially in a relationship in which Brazil and Paraguay had great ignorance of their political actions and military forces, and he will do so through the Imperial Legion at Assumpção. However, the response of the Minister who was there highlighted contributed to a false appreciation of the forces and reserves of the enemy, and therefore the formulation of an extremely optimistic plan. Paraguay had just reformed its fortifications under the supervision of foreign officials of the highest caliber, reforms which permitted comparisons with the most notable fortifications of the known world, for example, Sevastopol, Gibraltar, and Richmond. Admiral Tamandaré took steps to protect the principal and first affected, sent letters to the President of the Province of Mato Grosso to alert him of the Paraguayan intentions to start the conflict and did the same with the Commander of the Flotilla that was located in the region in order to minimize the damage, however the responses he received were somewhat melancholic. The Commander of the Flotilla stated that his Force was tiny and possessed of little firepower to contain an invasion. Responsible for our forces in Rio de la Plata, it was one of his concerns to notify the Minister of the Navy about the need to form a veritable fleet of transports to ensure the mobility of the Imperial Army by the region. It is possible to realize that for Tamandaré the war was already a reality and that the time until the first shot was given, the first charge