Irish Travellers (Irish: an lucht siúil, meaning 'the walking people') are a traditionally itinerant ethnic group who maintain a set of traditions. Although predominantly English-speaking, many also use Shelta. They live mostly in Ireland as well as comprising large communities in the United Kingdom and the United States. Traveller rights groups have long pushed for ethnic status from the Irish government, finally succeeding in 2017. As of 2016, there are 30,987 Travellers within Ireland. Travellers refer to themselves as Minkiers or Pavees, or in Irish as an Lucht Siúil ('the walking people'). 'Pikey' or 'pikie' is a slang term, which is pejorative and is a derogatory term aimed towards Travellers. It is used in the US, UK and Ireland to refer to Travellers. In a pejorative sense it means 'a lower-class person', perhaps 'coarse' or 'disreputable'. It is not well received among Irish Travellers or Romani, as it is an ethnic slur. The historical origins of Irish Travellers as a distinct group is still unknown. It continues to be the subject of academic and popular debate. Research has been complicated by the fact that the group appears to have no written records of its own. Deeper documentation of Shelta and the Travellers dates to the 1830s, but knowledge of Irish Travellers has been seen from the 1100s, as well as the 1500s-1800s. Many decrees against begging in England were directed at Travellers, passed by King Edward VI around 1551. One such decree was the “Acte for tynckers and pedlers”. The identity of Irish Travellers resembles other itinerant communities, some aspects being self-employment, family networks, birth, marriage, and burial rituals, taboos and folklore. Because they worked with metal, Travellers had to travel throughout Ireland and work on making various items such as ornaments, jewellery and horse harnesses to make a living. As a result, by 1175, they were referred to as “tinkler,” “tynkere,” or Tinkers, as well as Gypsies, all of which are derogative names to refer to their itinerant way of life. Many different theories have been put forward to explain the origins of Ireland's itinerant population. A suggestion that they might be of Romani extraction is not supported by genetic evidence, which finds no connection to Romani groups. One idea is of them being distantly related to a Celtic group that invaded Ireland. Another theory is of a pre-Gaelic (and therefore pre-Indo-European) origin, where Travellers are descended from a community that lived in Ireland before the arrival of the Celts. Once Ireland was claimed as Celtic, this group was seen as lower class. There is also a theory that an indigenous, itinerant, community of craftsmen are the ancestors of Travellers, and they never settled down like the Celts. Other speculations on their origin are that they were descended from those Irish who were made homeless during the Cromwellian conquest of Ireland in the 1650s, or made homeless in either the 1741 or the 1840s famine due to eviction.:56:43 It has since been recognised that no single explanation is likely to be adequate in answering this complex question. Current scholarship is investigating the background of Gaelic Ireland before the English Tudor conquest. The mobile nature and traditions of a Gaelic society based on pastoralism rather than land tenure before this event implies that Travellers represent descendants of the Gaelic social order marginalised during the change-over to an English landholding society. An early example of this mobile element in the population, and how displacement of clans can lead to increased nomadism within aristocratic warrior societies, is that of the Clan Murtough O' Connors, displaced after the Norman invasion.