Valentinian I struggled to maintain control over his empire.

Evidence

However, it was never easy for Valentinian to keep tabs on all the goings-on in his Empire, and devious local factions or officials could make the most of this, which is precisely what Romanus, the Comes of Africa, did in 363–4. — Stephen Kershaw, A Brief History of the Roman Empire, 1681

Categorization

• corroborated: 2 independent passages support this claim — Stephen Kershaw, A Brief History of the Roman Empire, 1681