Dictionary.com for "huckleberry" :
huckleberry
1670, Amer.Eng., probably an alteration of M.E. hurtilbery "whortleberry," from O.E. horte. Technically the fruit and plant of Gaylussacia, but also colloquially applied to the closely related blueberry. Slang meaning "person of little consequence" is attested from 1835.
Brad Paisley and wife named their firstborn "Huckleberry" too. I think it's William Huckleberry Paisley....or something like that.