From Academic Kids
Litha, the entire light half of the year, is centered upon Midsummer, with which it is easily identified, so that the summer solstice holiday is often referred to as Litha, especially in the recreated calendar used in the revived Germanic religion of Asatru. It is widely asserted that, in the pre-Christian Germanic calendar, the solstice was referred to as "Litha", a term especially endorsed by contemporary neopagans, but the term is specifically Anglo-Saxon.
Its widespread use as the name for this holiday may trace back only to its appearance in J. R. R. Tolkien's The Lord of the Rings trilogy, and its origins are specifically Anglo-Saxon. The only reference for the Anglo-Saxon calendar we have is Bede's De tempore rationum, written from a Christian perspective in the 8th century. Bede gives Anglo-Saxon names for the months of June and July Ærra Litha and Æftera Litha, the "foreLitha" and the "afterLitha", giving rise to the connection of the solstitial celebration as Litha.
- Byzant.com (http://www.byzant.com/festivals/litha.asp): Litha
- FactBites (http://www.factbites.com/topics/Litha): Litha
- Ron Hutton, The Pagan Religions of the Ancient British Isles
- Ron Hutton, 1996. The Stations of the Sun,(Oxford)