Zinfandel

Zinfandel's history was a genuine mystery for over a century, its origins untraceable through ordinary ampelography. DNA fingerprinting led by Carole Meredith in the 1990s and 2000s finally proved it genetically identical to southern Italy's Primitivo, and further research traced both back to a nearly extinct Croatian variety called Crljenak Kaštelanski, historically also known as Tribidrag. It is also a parent of Plavac Mali, Croatia's leading red, which it produced with the rare Dobričić.

Introduced to the United States in the early-to-mid 19th century, Zinfandel became closely identified with California, especially the old, dry-farmed vineyards planted by immigrant families in the late 1800s and early 1900s, some of which remarkably still bear fruit today. The grape is notorious for ripening unevenly within a single cluster, demanding careful vineyard management; it's also the base of the sweeter, pink "White Zinfandel" style, which — somewhat ironically — helped many of those historic old vineyards survive the late 20th century by giving growers a commercial reason to keep the vines in the ground.