Belenus (also Belenos, Belinus, Bel, Beli Mawr) is a Sun God from Celtic Mythology and, in the third century, the patron deity of the Italian city of Aquileia. Called the "Fair Shining One," (or The Shining God) he was one of the most ancient and most widely worshiped Celtic deities and is associated with the ancient fire festival and modern Sabbat Beltane. He was associated with the horse (as shown by the clay horse figurine offerings at Belenos’ Sainte-Sabine shrine in Burgundy) and also the Wheel. Perhaps like Apollo - with whom he became identified in the Augustan History - Belenos was thought to ride the Sun across the sky in a horse-drawn chariot.
There are 51 known inscriptions dedicated to Belenus, mainly concentrated in Cisalpine Gaul (Aquileia/Carni), Noricum and Gallia Narbonensis, but also extend far beyond into Celtic Britain and Iberia. Images of Belenus sometimes show him to be accompanied by a female, thought to be the Gaulish deity Belisama.
Tertullian writing in c. 200 AD identifies Belenus as the national god of Noricum. Inscriptions dedicated to Belenus are concentrated in the Eastern Alps and Gallia Cisalpina, but there is evidence that the popularity of the god became more widespread in the Roman period. The third-century emperors Diocletian and Maximian each dedicated an inscription to Belenus in the region of Aquileia. A further 6 votive inscriptions of Belenus were discovered at Altinum, Concordia and . The soldiers of Maximinus Thrax, who laid siege to Aquileia in 238, reported seeing an appearance of the god defending the city from the air.