There are probably nameholders with this spelling in every state in Europe, but this does not alter the fact that it is of Italian origin. Furthermore, it is not just Italian, it has three possible Italian origins. The first is locational, and describes literally one who lives by a pass or defile. Other surnames which have a similar meaning are Varchi, Vocatura, Serra and Malpasso. The second possibility is as a shortened form of Passa-Lacqua, which strictly speaking is a nickname for a water supplier (pass water), whilst the third possibility is a variant form of Iacopasso, itself a derivative of Giacomo (James). Italian surnames are the most complex in Europe, and the last to accept a fixed hereditary form, often not until the late 19th Century. In this case though Passo recordings date back to the early 17th Century, unfortunately the recordings do not explain the origins. An early example is Gioacchino Passo, christened at Silvano D'orbo, Allessandria, Italia, on December 17th 1635. The first recorded spelling of the family name is shown to be that of Pietro Passo, which was dated May 30th 1621, marriage to Anglea Bacigalupo, at Silvano' D'orbo, Italy, during the reign of Ferdinand 11, Holy Roman Emperor, 1619 - 1637. Surnames became necessary when governments introduced personal taxation. In England this was known as Poll Tax. Throughout the centuries, surnames in every country have continued to "develop" often leading to astonishing variants of the original spelling.