What was valens biggest accomplishments?

Valens, a Roman Emperor from 364 to 378 AD, is best known for his efforts to consolidate and defend the Eastern Roman Empire. His significant accomplishments include the establishment of a military presence along the Danube River to counter invasions by Germanic tribes and the construction of fortifications in key areas. Additionally, he convened the First Council of Constantinople in 381 AD, which was pivotal in shaping early Christian doctrine. However, his reign is often overshadowed by his defeat and death at the Battle of Adrianople in 378 AD.