Carignan is the grape which really distinguishes the red wines of the Languedoc and Roussillon from those of the southern Rhône (in the latter Grenache is ubiquitous and dominant, and Syrah and Mourvèdre are the preferred blending grapes).
It has been a much maligned grape. For example Jancis Robinson’s Oxford Companion to Wine thunders: "Carignan, late-ripening black grape variety which could fairly be called the bane of the European wine industry. ...distinguished only by its disadvantages".
So what’s wrong with it? Well, it can crop hugely, and produce vast quantities of acidic, tannic, rough red wine. As a result the French authorities used to pay for the up-rooting of Carignan: sadly, far too many old vines were pulled out.
But Carignan from old vines - at least 30 years old - pruned hard, and from hillside vineyards can produce splendid wine; deep coloured, tannic, spicy and with autumnal fruit which becomes meaty with age. It has a special affinity for schist, the foliated rock found all over the Languedoc and Roussillon.
Carignan was crossed to Cabernet Sauvignon to give Ruby Cabernet - a bastard grape if ever there was one.