The start of each new year has been celebrated for at least four millennia by civilizations all around the world. The earliest recorded celebrations date back to ancient Babylon, where the first new moon following the vernal equinox heralded the start of a new year. The occasion was celebrated with a large religious festival called Akitu. Even as ancient civilizations developed increasingly complex calendars, most cultures tied the first day of the year to a specific astrological or agricultural event. For example, for the ancient Egyptians, the new year began with the annual flooding of the Nile and the rising of the star Sirius, while for the ancient Chinese, the new year began with the second new moon after the winter solstice. In ancient Rome, the calendar was first created by Romulus, but over the years it fell out of sync with the sun. In 46 B.C., Emperor Julius Caesar introduced the Julian calendar, which closely resembled the modern Gregorian calendar that most countries around the world use today. As part of his calendar reform, Caesar declared January 1st as the first day of the new year, in part to honor the Roman god of new beginnings, Janus. The ancient Romans celebrated the new year by offering sacrifices to Janus, exchanging gifts, decorating their homes, and attending raucous parties. During the Middle Ages, January 1st was replaced as the first day of the year with more religiously significant dates, but in 1582, Pope Gregory XIII reestablished January 1st as New Year’s Day and it has remained so ever since. Today, many cultures celebrate the new year beginning on December 31, or New Year’s Eve, and continue their festivities into the early hours of January 1st. They also commonly gather together to celebrate during daytime hours on New Year’s Day. Common traditions include attending parties, enjoying special foods thought to bring good luck (beans and pork are both popular for this purpose in many cultures), watching firework displays, singing traditional songs such as “Auld Lang Syne,” and making resolutions. Interestingly, the practice of making resolutions is thought to date all the way back to the ancient Babylonians, who made promises as part of their celebration in hopes of pleasing the gods! Many people also participate in culture-specific or family-specific New Year’s traditions.