The article examines the activity of the statesman and president of Argentina Bartolomé Mitre (1821–1906), his plan of liberal modernization of Argentina. In his opinion, the remnants of the colonial structure were an obstacle to the progressive development of the country. To him and other liberals, the structure was barbarian. To remedy its corrosive effects, he proposed certain measures including active immigration and capital investment, the diversification of production, the modern banking system, the enlightenment of the people. Education was the basis of a democratic government. The major goal of the proposed political reform was to organize the nation. Bartolomé Mitre wanted to unite the nation but under the leadership of Buenos Aires which had a new role to play: to put civilization to work for the whole nation. Bartolomé Mitre saw the press as a significant tool of modernization provided it helped to raise the cultural level of the people, fought against the abuses of the authorities, called for the necessary reforms. Mitre was the first professional historian in Argentina. His great achievement was his studies of the War of Independence, “Historia de Belgrano у de la independencia argentina” and “Historia de San Martin у de la emancipación sudamericana». He saw the War of Independence as part of a universal historical process. The primary task of the historian, according to Mitre, was the discovery of new documentary sources which he called “meat on the bone of history”. For Mitre, the merit of a book was the number of documents used to write it. Using the term “documents,” he did not mean isolated papers but rather a coherent system of materials that contradict and correct each other. His ideas had a strong influence on Argentine historiography and determined the main directions of her development at the turn of the 19th – 20th centuries.