Sometimes the development of a modern surname surpasses all logical explanation - this is one of those occasions. 'Yersin' also recorded as Jerson, Youson, Gerston, Garston etc, is a dialectal development of the ancient Lancashire town name 'Garstang'. The name origin is Norse-Viking, deriving from the words 'geirr' meaning spear or spear head, and 'ston' - a pole. In effect it would have described a boundary marker between two control areas such as Lancashire and Yorkshire. Over the centuries as the surname travelled south, a combination of dialect and poor spelling completely altered its form. Examples of the recording include Robert Yerson who married Isabelle Tyffenne at St Giles Cripplegate, London on November 7th 1540, and Charles, son of Lewis and Sarah Yersin, christened at St Stephen Walbrooke, London, on July 30th 1740. The Coat of Arms has the blazon of a blue field, charged with three gold mascles, a silver chief, and a border engrailed in red. The first recorded spelling of the family name is shown to be that of Rogerus de Gerstan, which was dated 1379, in the Poll Tax Rolls of the county of Yorkshire, during the reign of King Richard 11, known as 'Richard of Bordeaux', 1377 - 1399. 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.