When I hear the name Casa Rosada I can't help but think of the Musical "Evita". However, I recently watched the Netflix movie "The Two Popes" and part of the back story in that movie was about an even more turbulent time in Argentina.
In March of 1976, a military junta took over the government in a military coup. It is believed that up to 30,000 people were killed or 'disappeared' by the military regime between 1976 and 1983.
Today the square is marked with tiles painted with the bandanas in the spot where mothers still march once a week over 40 years later.