Short history of the Celtic language family, by Meredith Richard (from the online version of the journal "Keltria: A Journal of Druidism and Celtic Magick").
A rather popular introduction to the languages and cultures of the Gaels, i.e. the people who now speak or who have spoken at one time any one of the three Gaelic languages: Irish, Manx, and Scottish Gaelic.
Sociolinguistics of the current situation of Celtic languages, with particular attention paid to the Gaelic tongues (Irish, Manx, and Scottish Gaelic).