Watch the C Tuning online guitar lesson by Cathy Fink from Clawhammer Banjo: Beginner Module 1
Pete Seeger uses this tuning a lot, though usually in lower keys with his long next banjo. It's a full sounding tuning for playing chords to accompany songs. It is also the tuning for "Classic Banjo" style.
In the early 1900's there was a lot of interest in banjo. Ragtime, classical and other genres were played on the banjo, often tuned like this gCGBD.