The use of surnames dates back only to the late Middle Ages, around the 14th century. Almost all 9th and 10th century records show only one name for individuals. A pattern began to emerge in the late 12th century with regard to references to manors, estates and monasteries. This presentation will show, through examples from many types of documents produced during the medieval period, how the Little Ice Age climatic downturn impacted living conditions and imposed what would have been a major impetus to identify people. The use of a surname became the favoured and logical method to do so.