Anastasius I reformed the coinage and the tax system, abolished a hated levy, and left the fullest treasury in Byzantine history to a successor he never chose.
Anastasius was a palace official of sixty when the empress Ariadne selected him to succeed her husband Zeno in 491, and married him. He ruled for twenty-seven years and was, by a distance, the most competent financial administrator to hold the office.
He abolished the chrysargyron, a tax on trade that fell hardest on the poorest, reformed the copper coinage into a usable system of denominations, and tightened tax collection without increasing rates.
The result was a reserve of some 320,000 pounds of gold at his death — the largest surplus in the empire's recorded history, and the fund that Justinian spent on Africa, Italy and Hagia Sophia within a generation.
He was born at Dyrrhachium about 431 and rose through the palace bureaucracy rather than the army, serving as a silentiary — an usher of the imperial chamber — which is an unusually quiet route to the purple.
He was known for religious opinions leaning towards the Monophysite position, which made his accession controversial and his reign quarrelsome: the patriarch required a written profession of orthodoxy from him before the coronation.
The byname Dicorus, "two-pupilled", comes from his having eyes of different colours, and is one of the few personal details about a Byzantine emperor that is simply physical description rather than propaganda.
The sources divide on him along religious lines and agree on his competence, which makes the portrait unusually reliable where it overlaps.
He is described as careful, patient, personally frugal and unusually accessible, and the abolition of the chrysargyron was greeted with public celebrations that suggest the reputation was earned.
His weakness was the same as his strength: he governed like an accountant in a century that required more. The Persian war of 502–506 caught him unprepared, and his religious policy — persistently sympathetic to the Monophysites — provoked riots in the capital and a serious revolt in Thrace under Vitalian.
The financial reforms are the substance. The chrysargyron went in 498; the copper coinage was reorganised the same year into marked denominations that made small transactions workable for the first time in generations; and the collection of the land tax was professionalised.
He fought Persia from 502 to 506 without decisive result, and built the great fortress of Dara on the Mesopotamian frontier — the position whose loss under Justin II would help drive that emperor mad.
He also built the Anastasian Wall across Thrace to protect the approaches to Constantinople, and spent his last years managing the revolt of Vitalian, who besieged the capital three times over the religious question.
The treasury is the legacy, and it is a larger one than it sounds. Justinian's reconquest of Africa and Italy, the building of Hagia Sophia and the codification of Roman law were all paid for out of a surplus that Anastasius accumulated and neither of his immediate successors could have generated.
The copper coinage reform outlasted the empire's territorial extent, and the fortress at Dara shaped the eastern frontier for a century.
He died without naming an heir, which handed the throne to whoever held the palace — and that turned out to be Justin, an illiterate peasant who commanded the guard.