Belenus
With the process of romanization, many Gaulish Gods in Northern Italy gradually lost their “celtic identity” and became more Roman, usually due to the heavy syncretism that happened in the region. Belenus is perhaps the most well known Deity in Italy that we have enough information to base a contemporary cult, and that has very clear evidence of Celtic heritage.
There are currently thirty-four inscriptions in His honor found on what it was the Cisalpine Gaul, with the variation between Belenus or Belinus.
He bears the titles of “Augustus” or “Defensor”, and is sometimes related to the God Apollo as “Apollo Belenus Augustus”. What makes the connection between the two Gods is that both are Celestials Deities of light and healing waters. In other inscriptions, offerings are made to Belenus in the company of Nymphs. Which indicates a connection to nature spirits, or at least spirits of water.
Belenus is known as “Defensor” for His role as the Patron God of Aquila, an Italian city that still exists today. So he can also be considered a protector God.
In contemporary personal (and shared) Gnosis of modern Gaulish Polythists, I’ve seen that the idea of Belenus as a God of Vitality is quite common. And I personally had similar experiences with Him on that matter.
But there is one single inscription of Belenus in Rome that is particularly interesting to me, found at Villa Adriana:
“Antinous and Belenus are equal in age and beauty
For this reason Antinous is also be worshipped like Belenus appropriately”
By Quintus the Sicilian
Antinous is also a God of healing and the pulse of life, and both are related to Apollo. As Antinous became the earthly vessel (As I like to say) to the Divine Mysteries of Vegetation, Death and Resurrection and Life everlasting, I feel comfortable with the Idea of Antinous absorbing the healing and life giver aspects of the God, forming a new cult of Antinous-Belenus, or even Antinous-Apollo-Belenus.
But as it is part of my personal Gnosis, Interpretation and cult, people who want a pure historical practice, are free to not consider his connection to Antinous.
Belenus, as a Gaulish Deity, is the God light, healing waters and life.
May He bring fulfillment and health.
And may He guide His followers with His divine light.
References

Gaulish coin of Apollo - Laténium museum

Apollo - William Blake
To Apollo Grannus - Deo Mercurio
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Belenos 101 | Nemeton Cunobelinus (wordpress.com)
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