The Endless Flame was a concept known to the Tkon civilization.
This ancient symbol of the Tkon Empire was among their culture since time immemorial. Amongst the old times of their race, their primal ancestors were said to had had prophets, mystics and seers whose visions according to archaic lore prove to had been instrumental in the formation of the dynasty. By latter era, the leader of the Tkon Empire needed no such ocular visions and it became a symbol of their race. (TNG novel: Q-Zone)