This surname which comes via the Latin EPISKOPOS meant an overseer from EPI (on, over) and SKOPEIN (to look). The Greek word was adopted early in the Christian era as a title for an overseer of a local community of Christians and has yielded variant spellings in every European language. The name came to be applied as a surname for a variety of reasons, among them service in the household of a bishop, supposed resemblance in bearing or appearance to a bishop, and as 'boy bishop' on St. Nicholas day. The origins of Italian surnames are not clear, and much work remains to be done on medieval Italian records. It seems that fixed bynames, in some cases hereditary, were in use in the Venetian Republic by the end of the 10th century. The typical Italian surname endings are 'i' and 'o', the former being characteristic of northern Italy. The singular form 'o' is more typical of southern Italy. The earliest French hereditary surnames are found in the 12th century, at more or less the same time as they arose in England, but they are by no means common before the 13th century, and it was not until the 15th century that they stabilized to any great extent; before then a surname might be handed down for two or three generations, but then abandoned in favour of another. In the south, many French surnames have come in from Italy over the centuries, and in Northern France, Germanic influence can often be detected. During the Middle Ages, when people were unable to read or write, signs were needed for all visual identification. For several centuries city streets were filled with signs of all kinds, public houses, tradesmen and even private householders found them necessary. This was an age when there were no numbered houses, and an address was a descriptive phrase that made use of a convenient landmark. At this time, coats of arms came into being, for the practical reason that men went into battle heavily armed and were difficult to recognise. It became the custom for them to adorn their helmets with distinctive crests, and to paint their shields with animals and the like. Coats of arms accompanied the development of surnames, becoming hereditary in the same way.