Nerva–Antonine dynasty
Bassus was of Italian Roman and Pontian Greek ancestry, who came from a distinguished senatorial family. Bassus was the son of an elder Pomponius Bassus, the Senator who served as consul in 211 and Annia Aurelia Faustina, who was the great-granddaughter of the Emperor Marcus Aurelius and Faustina the Younger. His sister was Pomponia Ummidia and through his mother, Bassus was a descendant of the Nerva–Antonine dynasty.