Cabal is also related to cannibal.
The word does seem to derive from the French: cabale which meant 'intrigue'. Etymology connects the word with Hebrew QBLH - but the Hebrew (Kabbalah) means 'to receive'.
It is misleading to identify Kabbalah, the Jewish mystical rabbinical works on Scripture as secret or intrigue; they tended to be a separate group because of their attempt to discern 'the deeper' understanding of the ancient Scriptural texts - but they published their results openly. The Jewish Encyclopedia equates QBLH with the Talmud, that dealing with the interpretation of Biblical laws and traditions, QBLH dealing with the interpretation of deeper, hidden spiritual meaning. The French term came to be associated with secret groups seeking to influence - overthrow - a government.
The Jewish approach to QBLH has spawned Christian Kabbalists - of which I am one - who would likely also be termed 'mystics'. I have web posted some abbreviated personal interpretations myself, especially my page concerning Biblical use of numbers. 🙂
The Germanic tribes before 800 were primarily versions of what you likely think of as the Norse religion. It was somewhat different but details are hard to know because they didnt write anything down and much of what we know is inference or imaginative speculation by those that came after with only a bit of documentation from foreigners to back it all up.