Approximately 3,000 years ago, the echidnas thrived as a clan known as the Knuckles Clan in what would become the Mystic Ruins. After incurring the wrath of Chaos however, much of the Knuckles Clan was wiped out. 

For most of the echidnas, I'd say go for something similar to a nigerian or something, just something that sounds like it's part of a tribe.