Manuel Luís Osório, Marquis of Erval was a Brazilian military officer, monarchist and politician. A member of the Imperial Army at the age of fifteen, he climbed all the posts of the military hierarchy of his time thanks to the soldier attributes that consecrated him as "The Legendary". He participated in the main military events of the late nineteenth century in the Río de la Plata region and is considered a hero of the Paraguayan War. He was declared patron of the Cavalry Branch of the Brazilian Army in 1962.

The Imperial Brazilian Army was the name given to the land force of the Empire of Brazil. The Brazilian Army was formed after the independence of the country from Portugal in 1822 and reformed in 1889, after the republican coup d'état that created the First Brazilian Republic, a dictatorship headed by the army.