Plaza San Martín (English: San Martín Square) is a park located in the Retiro neighbourhood of Buenos Aires, Argentina. Situated at the northern end of pedestrianized Florida Street, the park is bounded by Libertador Ave. (N), Maipú St. (W), Santa Fe Avenue (S), and Leandro Alem Av. (E). Its coordinates are 34°35′42″S 58°22′32″W / 34.59500°S 58.37556°W.
A succession of colonial Spanish governors had their official residences built on what today is the plaza and, in 1713, the land was sold to the British South Sea Company. The South Sea Company operated their slave trade out of the former governor's residence and a fort and bullring were later built nearby. The land was the site of Gen. John Whitelocke's 1807 defeat upon Britain's second attempt to conquer Buenos Aires, whereby the area became known as the "Field of Glory". The Revolution of 1810 brought an autonomous government to Buenos Aires, which entrusted the Mounted Grenadiers to José de San Martín and allowed him to establish his main barracks at the plaza. An 1813 resolution abolished the slave trade in the United Provinces of the Río de la Plata and the slave quarters were shuttered. Following his decisive military victories, Gen. San Martín was forced into exile in 1824 for political reasons; but a reappraisal of his place in history led to his becoming nearly eponymous in Argentina after his death in 1850. Accordingly, French sculptor Louis-Joseph Daumas was commissioned in 1862 to create an equestrian statue of the hero of the Wars for Independence and the square was renamed in his honor in 1878, upon the hundredth anniversary of his birth.