Originally only an "exceptional" tax (i.e. imposed and collected in times of need, as the king was expected to survive on the revenues of the "domaine royal", or lands that belonged to him directly), the taille became permanent in 1439, when the right to collect taxes in support of a standing army was granted to Charles VII of France during the Hundred Years' War. Unlike modern income taxes, the total amount of the taille was first set (after the Estates General was suspended in 1484) by the French king from year to year, and this amount was then apportioned among the various provinces for collection.
