Lot of Huguenots came from the Midi (Languedoc, Provence, Cevennes), the Massif Central, and the Atlantic coast (La Rochelle was their capitol for a while). There were also "Walloons" from northeastern France (Artois).
As for the Catholic French Canadians, most were from Brittany, Normandy and the Paris Basin (Quebecois) and Poitou-Charentes (Acadians).
Huguenot family names in South Africa seem to be centered on Provence (Joubert, Malan) and Auvergne (Villion/Viljoen). The Huguenots held out in the Cevennes region of Southern France, where Huguenot insurgents fought the Catholic French army for 20-30 years after the Edict of Nantes was revoked in 1685.
As for whether the Huguenots are or were Germanic, their descendants in Germany, South Africa, Holland and Sweden are, but the 16th-17th century Huguenots were French-speakers, and some came from regions of France (e.g. Provence) that were little affected by the Germanic invasions.