Constantinian coinage: the most-found Roman in Britain

The Constantinian dynasty (306–363) produced the single most common identifiable Roman coin found in Britain — small AE3 and AE4 bronzes from the reformed nummus standard, struck in vast quantities and flooded into Romano-British circulation. If you’ve dug a small 14–18 mm bronze with a diademed bust on the obverse, the odds are heavily that it’s Constantinian.

Who was Constantine?

Constantine I (the Great, reigned 306–337) was the emperor who legalised Christianity, founded Constantinople as a new imperial capital, and reformed the Roman coinage with the new nummus denomination after Diocletian’s earlier reforms. His sons Constantine II, Constantius II, and Constans I continued striking in his style until 361, and Julian (the Apostate) closed the dynasty with a brief pagan reaction in 361–363.

The Constantinian family

The dominant reverse types

Five reverses between them account for most UK-found Constantinian coins. For full visual references see our Roman bronze reverses guide.

Mintmarks — where your coin came from

Late Roman bronzes carry a mintmark in the exergue (the space below the reverse design). UK finds skew heavily to the western mints, with London striking from 296 until c.325 before its mint was closed, and Trier dominating thereafter.

Reece period 17 — the British coin supply

Richard Reece’s chronological framework assigns most Constantinian small bronzes to Reece Period 17 (330–348). This period sees an enormous coin supply reach Romano-British circulation — partly because Britain was a productive province in the 4th century, and partly because the small AE3 / AE4 fractions were the only practical small change for everyday transactions. Reece Period 17 finds typically outnumber every other Roman period on UK sites by a factor of two to one, sometimes more.

Procedural identification

1. Confirm small bronze.14–18 mm, ~2–3 g, green-brown patina, copper-alloy.
2. Diademed bust?Pearl band tied at the back with dangling ties → Constantinian (c.317 onwards). Laureate or radiate → earlier dynasty; see our emperor by bust guide.
3. Read the reverse type. Two soldiers + standards (GLORIA EXERCITVS) is the dominant Reece-17 type. Wolf and twins is VRBS ROMA. See the type table above.
4. Count the standardsfor GLORIA EXERCITVS to split 330–337 (two) from 337–348 (one).
5. Read the obverse legend for emperor identity. Even partial: CONSTANTIN... = Constantine I or II; CONSTANTI... = ambiguous (any of the three); CONSTANS... = Constans.
6. Read the mintmark in the exergue. Together with the reverse this gives a precise attribution.

Barbarous imitations

The Constantinian small bronzes were imitated locally in Britain during periods of supply shortage, particularly after the closure of the London mint c.325 and into the late Constantinian period. Barbarous nummi typically:

• Are slightly smaller and lighter than official issues
• Show crude execution — blundered legends, simplified figures
• Often imitate GLORIA EXERCITVS or VRBS ROMA reverses
• Have illegible or invented mintmarks

Barbarous radiates (RP 13, 260–275) and barbarous nummi (later 4th c.) are separate phenomena but both reflect periods when official coin supply couldn’t keep up with British circulation demand.