Thor - Norse God of Thunder and Storms. Is it any wonder that the God of Thunder and Storms is honored at midsummer? Especially here in the prairies, where thunderstorms rolling across the sky are common. Thor is also a God of fertility, because without the storms he brings crops would wither in the fields.
Apollo - God of, well, everything! Apollo was a Sun God, as well as being a patron of music, poetry, art, and medicine. He is the brother of Artemis. Apollo is honored at this time not only because he is a Sun God, but because he is also defender of the herds and the flocks.
Any Sun God or God of Fertility can be honored at Litha - The Oak King, of course; as well as Osiris, Ra, Ares, Dagda, and many more. Which Gods do you honor at Litha?