Mainline Western religious traditions teach that everything that happens more or less happens because a god is in charge, whether it’s the Hebrew El Shaddai, the Christian Jesus or the Islamic Allah. But long before those traditions were born, our earliest ancestors believed pretty much the same thing. While the idea of a single high god is rooted in the most ancient of Hebrew traditions and then later co-opted Christianity and Islam (both of which are rooted in the Hebrew bible), the idea that there are divine or spiritual entities in charge of what makes the world go around is very ancient and the high god is merely the evolution of that more ancient idea.
But, what does all that have to do with the Leitha and Yule? For many pagans, Leitha is seen as the battleground between the Oak King who rules from mid-winter (another name for Yule) to mid-summer, or Leitha, and the Holly King who rules over the other half of the year. These gods don’t exist in eternal harmony but rather they annually supplant one another. The Oak King rules that half of the year where the days grow longer while the Holly King, whose reign ends at Yule, rules over that part of the year where the days grow continually shorter. As the gods rule over their respective seasons, what goes with the seasons goes with the gods. Summer, at least the vegetation dies when winter takes over but is reborn again the following year. And so does the Oak King.
While we assume, without any verifiable evidence, mind you, that our earliest ancestors took those stories at face value, Modern pagans probably do not. I know I certainly don’t. But, pagan spirituality is earth based which means that divinity resides in nature and the mythologies, while not taken at face value, mythology nevertheless give a definitive language to express that relationship.
While there are, no doubt, other mythologies in this world that give context and meaning to the summer solstice, to merely celebrate it as an astronomical fact is to fall victim to the mechanical universe clock work fallacy. And it is certainly not pagan.