Frontinus

Sextus Julius Frontinus rose through the ranks as a novus homo in the late 1st century AD, a man without aristocratic lineage who reached consul three times on merit. He commanded legions under Domitian in Roman Britain and along the Rhine and Danube frontiers, winning enough to be trusted with the empire's trickier borders. Later he took on administrative posts under Nerva and Trajan, the quiet work that keeps an empire running. But it's his technical writing that outlasted the campaigns: De aquaeductu, a treatise on Rome's aqueducts, recorded the system's engineering in enough detail that centuries later people still read it to understand how Rome moved water. He died around 103 AD, more read by posterity than he likely expected.