The first planned city in the country of the republican period and projected to be the new capital of Minas Gerais, the “Minas City” (Cidade de Minas), as the capital was known in the past, was inaugurated on December 12th, 1897. The name “Belo Horizonte” was definitively adopted four years later, in 1901. Read more about Belo Horizonte.
You may also find intesting Daniel L. McDonald’s MA thesis in which he argues “that the decision to move the capital of Minas Gerais at the outset of the First Republic and the designing of the new city encompassed an evolving vision of modernity that helped establish the planned city as a means to transport Brazil into the future”.
General plan of the city of Belo Horizonte (1895)