Primitivo/Zinfandel are identical twins.  The name Primitivo means primitive.  But it actually stems from the word primitivus, meaning early, because it ripens earlier than most other red grapes. Mike Grgich, who was born in Croatia, founded the Zinfandel Advocates and Producers in 1991.  In trying to create awareness about Zinfandel, and in thinking it was the same grape as his native Plavac Mali, according to ampelography (the study of leaves), he consulted experts and DNA evidence was collected.  A UC Davis professor thought Primitivo was a lot like Zinfandel and the evidence concluded that they are identical twins.  Zinfandel is a parent of Plavac Mali, and same grape as Crljenak Kaštelanski.  Ampelography archeological evidence found existence of cultivation in Croatia from around 6000 BCE, older than anywhere else.  So, Zinfandel began in the heart of the beginning of viticulture and from there it spread throughout the Mediterranean.  It went to Italy from Croatia via monks where it was head trained in lava rock and called Primitivo in Puglia, Italy.  It was thought so well of that Primitivo was requested by name in the 1800’s as part of the dowries for the Dons and Countessas.  Simultaneously Zinfandel travelled to Austria and Hungry and there it is called Zeirfandler and trained in fertile soils on trellises.  When the Imperial Austrian Nursery sent a Prince to California during the Gold Rush, it was labeled as Zinfandel.  In England it’s called Black St Peters.  Phylloxera wiped out all but 9 vines in Europe.  It has uneven veraison so it takes a loving viticulturalist to determine the style.   In cooler areas, it takes on lighter raspberry notes with more acidity.  In warmer areas it takes on heavier strawberry and blackberry notes with less acidity.   When Primitivo is head-trained it produces smaller berries with more chocolately-anise aromas. So, although, Zinfandel and Primitivo are identical twins, over the last 2500 years, they are different in body, acidity and flavor profiles.  European Union recognized them as the same for labeling purposes in 1999.