copy and paste:Originally Posted by Tibbs
While we're here, we should mention the capitalized term Middle Ages. The Middle Ages can be loosely defined as the time in European history between classical antiquity and the Renaissance, or roughly from the late fifth century to the fifteenth century, but again, this is a fluid range. Sometimes the Middle Ages are held to begin around A.D. 1000, with the earlier period being the Dark Ages, and the end of the Middle Ages can be variously reckoned as 1350, 1400, 1450, or 1500. It's also worth noting the curiosity that English is one of the few languages to interpret "Middle Ages" as a plural; the equivalents in most other languages, as Medieval Latin medium aevum, French moyen âge, German mittelalter, and Italian il Medioevo are all singular.
Sounds like it's OK to capitalize it.
took it from: