Zagmuk, Ancient Mesopotamia
Zagmuk is the oldest solstice celebration on written record, observed in Mesopotamia about 5,000 years ago. It commemorated the sun god Marduk's battle against the forces of chaos and destruction. We can't recommend celebrating it enough. Zagmuk customs include acting out wars between gods, masquerades aplenty, and tons of feasts and gift-giving. Interestingly, it also had a powerful anti-authoritarian streak: the royals publicly renounced their titles for the entire festival, and like Saturnalia, masters served their slaves. If there's a better way to celebrate the holidays than stuffing our faces and acting out divine battles, we don't want to know about it. Pictured: the god Marduk on a stamp.