Empire in Brazil: A New World Experiment with Monarchy (1958) by C. H. Haring
The author’s analysis of why the ruling family of Portugal failed in implanting the monarchy in Brazil. Some of the subject matter includes the loss of support from the armed forces and the abolition of slavery as keys to loss of support for the monarchy and the fall of Dom Pedro II.
Dom Pedro was indeed a popular monarch and very much appealed to the common people. However these were not the people pulling the strings in Brazil. Planters upset with the loss of their property (slaves) and generals upset with his decisions made the throne unstable. Dom Pedro II was a liberal, well intentioned monarch, but proved unable to pass on his throne.