My most common dance is known as 'the set' where I live in W.Clare, Ireland. It is widely danced & taught internationally as the 'Caledonian' set and is one of many such sets which have been danced in Ireland for 150 odd years. No one really seems to know how it got its name but it is widely thought to have had some influence from Scottish soldiers who were stationed here in the 19th/20th C.

There is much info. availabe on the 'Set Dancing News' website.
http;/www.setdancingnews.net