Briar pipes were an advance of the 19th century.
This is from Iain Gately's "Tobacco":
"Some years after [Napoleon's] death, a Bonapartist pilgrim to the tyrant's birthplace in Ajaccio broke his pipe and requested a passing Corsican peasant to make him another. The peasant carved the pilgrim a pipe bowl from a local wood - Erica Arborea or 'bruyere' - which functioned as effectively as his broken meerschaum. Inspired, the pilgrim sent samples of the same wood to his usual pipe-makers in St-Claude, near France's Jura mountains, who realized their potential and manufactured them commercially. Briar pipes, as these wonders were known in England, became available in the 1850s and were an immediate success."
You can come to one of two conclusions from this passage: there was an isolated Corsican tradition of briar pipe making OR the Corsicans simply used the wood for another purpose and this individual became creative when he was commissioned to carve the visitor a pipe...
The quote does, however, demonstrate that meerschaum pipes have been commercially available for longer than briar and that briars were not mass produced until the middle of the century.
Unless you are portraying the character of a Mediterranean peasant after the introduction of tobacco to the Old World then there wouldn't be a chance that one was smoking a briar...