- Vassal of King Pedro of Portugal.
- Brother of João Mendes de Vasconcelos. [Pedro, 27: 21-22]
- Maternal uncle of Queen Leonor Teles. [João1, ch.73]
- Witnessed King Pedro in Cantanhede swearing on the Gospels that he had married Dona Inês de Castro. [Pedro, ch. 27: 20-25]
- Accompanied Gil Fernandes de Carvalho, the Master of Santiago in Portugal, as well as Martim Vasques de Góis, Martim Afonso de Melo, Álvaro Gonçalves de Moura, Nuno Viegas the Elder, and Rui Vasques Ribeira to assist Pedro of Castile in the siege of Tarazona. They were sent by King Pedro of Portugal, Pedro of Castile's uncle. [Pedro, ch. 34: 39-46]
- King Fernando appointed him as 'fronteiro', deffender of Lisbon in 1382 when the Castilian fleet of Juan I attacked the city once again. [Fernando, ch. 135: 5-7]
Gonçallo Meendez de Vaasconcellos