When did Buenos Aires become the capital of Argentina?
Buenos Aires
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During most of the 19th century, the political status of the city remained a sensitive subject. It was already the capital of Buenos Aires Province, and between 1853 and 1860 it was the capital of the seceded State of Buenos Aires. The issue was fought out more than once on the battlefield, until the matter was finally settled in 1880 when the city was federalized and became the seat of government, with its mayor appointed by the president. The Casa Rosada became the seat of the president.[23]