Recorded in many forms including Imm, Imms, Im, Ims, Immison, Imos, Imossen, Impson, Imeson, Immins, Immings, and probably others, this is an English medieval surname. It originates from the female personal name Emma, itself a shortened version of Germanic given names such as Ermentrude, Ermyntrude, and Ermin meaning "entire" fused with "drudi" meaning strength. The first name was introduced into England by the Norman-French after the Conquest of 1066, amongst whom it was extremely popular. Female names from which developed surnames (metronymics) are not unusual, although much rarer than patronymics, which form the largest grouping in the surname lists. The reasons as to why a son should take his mothers name are very varied, but include the death of the father leaving the mother as the estate holder, or the simple fact that some women were much wealthier than their husbands. Early examples of recordings include Thomas Imme of Somerset in the year 1243, and Geoffrey Imme of Surrey in 1332. Later examples include George, the son of Thomas and Hannah Imeson, who was christened at St. Sepulchre, London on March 14th 1730 whilst Ann Imison married William Lees at St. Martin in the Fields, Westminster on January 9th 1798. 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.