Born on the island of São Jorge, in the municipality of Velas, he was also referred to as João Teixeira Soares.

In October 1849, he entered the University of Coimbra on the mainland of Portugal, where he earned the Bachelor of Mathematics degree in 1853 and a Doctor of Philosophy the following year.

The methodical and painstaking work involved the transcription of numerous historical documents, and the discovery of other rare references that he used in his articles on local history.

A fellow Azorean, Braga shared Teixeira Soares's passion for folklore and other aspects of traditional culture.

Teixeira Soares contributed his collection of the songs of São Jorge and was one of the chief collaborators on Braga's pioneering work, Cantos Populares do Archipelago Açorian ("Popular Songs from the Azorean Archipelago").