This apparently obvious surname is very deceptive. It would seem to be locational and as such probably Scottish from the Isle of Arran, however this is almost certainly not the case. The name is recorded in England and specifically in the registers of the city of London and the surrounding areas since the time of King James 1st of England and V1 of Scotland, when he ruled the joint kingdoms from 1603 to 1625. However at that date the spelling was 'Erin', with John Erin marrying Clementine Mountford at the church of St Giles by St Pauls, on September 10th 1624. By 1653 the spelling had 'developed' to Arine, when Judith Arine married John Roberts at the church of St Martin Ongar, city of London. In 1697 came a further 'dialectal' change when Mary Arrens married John Lyon at the church of All Hallows, London Wall, whilst half a century later we find the 'modern' form, when Mary Arran married John Arnall at the church of St Lawence Pountney, also city of London. If the original spelling of 'Erin' is correct, this may suggest that the nameholder came from the town of Port Erin in the Isle of Man or possibly from Erinoch in Scotland. Locational surnames were 'from' names. That is to say that they were given to people after they left their original homes and moved elsewhere.