Werner Eck has stated that he was from Arelate, but certainly came from Gallia Narbonensis; Silvanus was the son of the senator M. Pompeius M.f.
[1] The additional three nomina of his name -- "Silvanus Staberius Flavianus" -- is due to either a testamentary adoption, or comes from his mother's family.
[3] After returning to Rome Silvanus was charged for actions related to his governance but was acquitted by the Emperor.
Tacitus describes him as "rich and advanced in years",[5] which was likely what Galba wanted: a complacent non-entity overseeing an important province.
However, he proved pliable by the legatus legionis Lucius Annius Bassus, who encouraged him to support Vespasian at the critical moment.