Little is known about the calendar used by the Nephites, but it is clear that they did classify their history based on years, months, and days. It is perhaps plausible that like many other agricultural societies, they used the lunar calendar (Coriantumr’s stay in Zarahemla was reportedly “nine moons.”) When the government of Zarahemla switched from a monarchy to a judicial system, the years came to be numbered according to the elapsed time under “the reign of the judges.” References to dates, months and years are sporadic, but we do get one clear look into some dramatic events that occured on new year’s eve between the 25th and 26th years of the reign of the judges.

Amalickiah, an ex-Nephite with an oath to drink the blood of Captain Moroni, had taken control of the Lamanite army and advances into the land of Zarahemla. The first city to fall is the coastal city of Moroni. Amalickiah conquers nearly all of the eastern cities, and begins to move towards Bountiful when he encounters Teancum’s troops. They battle until dark, then they retreat to their camps. That night, Teancum sneaks into the enemy camp, finds Amalickiah sleeping, and kills him with a swift javelin strike. “And thus endeth the twenty and fifth year.”

Mormon tells us that the following day was the “first morning of the first month,” or new year’s day. The Lamanites awake to find their commander dead in his tent. Being new year’s day, there possibly were some rites or rituals that required the sovereign’s participation; the timing of Teancum’s attack surely amplified its magnitude, throwing the entire Lamanite military into disarray. The Lamanites subsequently abandon their campaign to occupy Bountiful and instead retreat to the city of Mulek.

One other interesting thing to note about this story is that the new year’s eve battle resulted in “much fatigue, which was caused by the labors and heat of the day.” This is a telling clue about the climate of Book of Mormon lands. If new year’s eve is associated with blistering heat, then we are most likely not dealing with a North American climate and/or our Gregorian calendar.