Known as Día de la Revolución de Mayo, this holiday is always celebrated on May 25, regardless of the day of the week.
Anniversary of the First Independent Government in Buenos Aires. On May 25 1810 a small revolution took place in Buenos Aires. This was the first step towards independence.
The May Revolution wasn't a so much of a revolution but more the evolution of a sequence of political and social events in Buenos Aires during the early part of the nineteenth century which led to the first local government not designated by the Spanish Crown in the region known as the Viceroyalty of the Río de la Plata, which at the time contained the present-day nations of Argentina, Bolivia, Paraguay and Uruguay.
Although the Revolution took place in Buenos Aires, one of the consequences was that the head of the Viceroyalty was ousted from office.
There was no great violence involved; the term "revolution" has been loosely applied by Argentine tradition to highlight the changing of their governmental system and distinguish the undisputed fact that after the May Revolution, Buenos Aires itself was no longer subservient to decisions taken by Spain in their name.