Legatus Augusti pro praetore

A legatus Augusti pro praetore (lit. 'envoy of the emperor – acting for the praetor') was the official title of the governor or general of some Imperial provinces of the Roman Empire during the Principate era, normally the larger ones or those where legions were based. Provinces were denoted imperial if their governor was selected by the emperor, in contrast to senatorial provinces, whose governors (called proconsuls) were elected by the Roman Senate.

Source: Wikipedia — Legatus Augusti pro praetore (CC BY-SA 4.0)