Gaelic, or Goidelic, is a language that belongs to the Celtic branch of the Indo-European language group. It is spoken in Ireland and in the Highlands of Scotland, and it has two main dialects: Irish and Scottish Gaelic. Manx, which was once spoken on the Isle of Man but is now nearly extinct, is also a Gaelic dialect. Irish is the most important of the dialects. It has a considerable body of literature that probably dates as far back as the 5th century A.D., whereas there are no Scottish Gaelic or Manx writings from so early a period.
It is believed that Gaelic spread to Scotland from Ireland in the 6th century A.D. There was no marked difference between spoken Irish and Scottish Gaelic until about the 13th century. Until the 17th century, Irish was used for literature in Ireland and in Scotland. Scottish Gaelic, which is distinguished from Irish mainly because of its strong Norse elements, is now spoken by about 100,000 people.
In the 19th century, when Gaelic had almost died out, societies were organized in Ireland to promote the revival of the language. In 1893 the Irish scholar Douglas Hyde founded the Gaelic League. The league established a weekly newspaper in Gaelic and stimu lated the publication of Gaelic textbooks and other literary works. Since 1922, Gaelic has been one of Ireland's official languages, and it is a required subject in the public schools. Gaelic is spoken at present by more than half of the Irish people, and most of these also speak the dominant tongue, English. English is more widespread than Gaelic in both Ireland and Scotland.