Zagal is a knitting and crochet yarn produced exclusively from the wool of Portuguese Merino sheep, an indigenous breed found in the south of Portugal, especially in the Alentejo. The Merino breed originated in the Iberian Peninsula, possibly before Roman times, and has always been highly prized by its finesse and softness.

For centuries this Iberian wool was traded all over Europe while Merino sheep were subject to strict laws that kept the breed exclusive to the peninsula. The Portuguese Merino Breeders Association (ANCORME) verifies the origin and quality of the fleece used to produce this yarn.