General Osório Square was designed by José Antônio Moreira Filho, 2nd Baron of Ipanema (1830–1899), founder of Vila Ipanema, the precursor to the present-day neighborhood.

The square was formerly called Praça Ferreira Viana, and later Praça Marechal Floriano Peixoto, In 1922 it was renamed in honor of Manuel Luís Osório, Marquis of Erval (1808–1879), a Brazilian military officer during the Paraguayan War.

Numerous artists of the period, including Nelson Leirner, Flávio Mota, Carlos Scliar, Hélio Oiticica, and others, decorated the square with textile art on the eve of Carnival.

While the happening was not overtly political and attracted little attention from the military police, it closely predated the murder of Edson Luís de Lima Souto in March 1968 and the subsequent March of the One Hundred Thousand against the violence of the military regime.

[3] The Sunday Hippie Fair (Feira Hippie de Ipanema) at General Osório Square, a weekly art fair, dates to the same year.