Why did Caesar use Roman names for Gaulish gods?

In his Commentarii de bello Gallico, Julius Caesar referred to Gaulish gods by the names of Roman deities in a practice known as interpretatio Romana ("Latin translation").12

Rather than using native names, Caesar equated Gaulish figures with Roman gods whose functions and attributes were familiar to his audience. This approach allowed him to describe the Gaulish pantheon through a recognizable, schematic framework, effectively "translating" foreign deities into a classical context. For example, he identified the most honored Gaulish god as Mercury, citing his role as an inventor of arts and patron of commerce, and equated others with Apollo, Mars, Jupiter, and Minerva based on their perceived roles in healing, war, or governance.12

While this method provided a convenient, albeit simplified, catalog for Roman readers, it complicates modern efforts to identify specific Gaulish deities. The practice often obscured the nuanced, local, or non-compartmentalized nature of Celtic religious figures, as the Roman equivalents did not always perfectly align with the complex, multifaceted roles held by the gods in native tradition.12