January 29 – Platine War: Battle of Alvarez Field. 4,000 Rosas loyalist Argentine troops led two of General Ángel Pacheco's colonel defeated by anti-Rosas forces.
January 31 – Two anti-Rosas divisions defeat Pacheco's forces at the Battle of Marques Bridge
February 1 – anti-Rosas coalition camps 9 km (5.6 mi) from Buenos Aires
February 2 – brief skirmish between anti-Rosas coalition and Rosas loyalists end with loyalists retreat
February 4 – surviving soldiers of Regimento Aquino, composed of Rosas loyalists who had defected from anti-Rosas coalition, summarily executed by firing squad