Denial implies no beginning.
If uncreated and linear it is unendingly long, backwards. This seems to me to be close to the position of uniformitarianism and many theistic evolutionists today. If uncreated and cyclical we get eternal return, which is probably the most consistent way to look at Heraclitus, Aristotle and Hegel, as well as many Oriental philosophies of history. Eternal return implies that history repeats itself in a literal sense. Nothing is ever new, progress is illusory.