The Anemodoulion, a Constantinopolitan tetrapylon decorated with numerous figural reliefs and crowned by a weathervane, has traditionally been seen as an entirely late antique construction. A re-evaluation of the medieval sources shows that, while the tetrapylon itself was constructed in late antiquity, its figural decoration and conversion into a weathervane likely date to the reign of Leo III (717–741). Viewed in connection with other monuments of Leo's reign, in particular the gate of the Kontoskalion Harbor, and historical accounts of the (...) end of the Arab siege of 717/18, the Anemodoulion may be interpreted as a triumphal monument celebrating the dispersal of the Arab fleet via a powerful storm. It thus provides new insight into the earliest efforts of the Isaurian emperors to rebuild Constantinople as a fitting capital for a medieval empire. (shrink)