Portugal and Brazil
See also: Portuguese name and Portuguese naming customsPortugal and Brazil, as Portuguese-speaking countries, use Portuguese naming customs, in which the order of multiple family names is usually reversed from that of Spanish—with the mother's maiden name preceding the father's surname.
Complete names are formed generally as in Western Europe, i.e., by first names, followed optionally by one or more middle names, followed by the mother's family surname, followed by the father's family surname. However, it is quite common for a person to go by one of their surnames which is not the last one in order, especially if it very common. For example, someone called João Cavaco Oliveira can be commonly called "Cavaco" and Ayrton Senna da Silva chose to be known just as Ayrton Senna because Silva is a very common surname.
Read more about this topic: Middle Name