From the Kabbalah FAQ ( http://digital-brilliance.com/kab/faq.htm )
    "Kabbalah is an aspect of Jewish mysticism. It consists of a large body of speculation on the nature of divinity, the creation, the origin and fate of the soul, and the role of human beings. It consists also of meditative, devotional, mystical and magical practices which were taught only to a select few and for this reason Kabbalah is regarded as an esoteric offshoot of Judaism. Some aspects of Kabbalah have been studied and used by non-Jews for several hundred years (Hermetic Kabbalah)."

Although some of its founding books have been written in Antiquity, Kabbalah sensu stricto is thought to have appeared in XIth century France and spread over all of Europe (most notably Spain). Increasing persecution of European Jews in the Middle Ages (most notably the expulsion of the Jews from Spain in 1492) led to a strong emphasis on messianism, culminating into the self-contained cosmogony of Isaac Luria - a triumph of Theology. Hassidism has often been related to Kabbalah.