The name Herga derives from the Old English (Anglo Saxon) hearg which meant a place of worship/shrine/temple. Modern place names Harrow usually come from this. Harrow in Middlesex (the place referred to here, home of the Herga Folk Club in NW London) was at one time Gumeningas Herga , meaning the worship place of either a man called Gumeninga or a tribe called the Gumeningas. (IIRC). (So the root is Germanic rather than Latin).

Mick