As the clock prepares to strike midnight on December 31st, 2025, heralding the arrival of 2026, many are only just discovering the ancient and surprisingly pragmatic reason our year begins on January 1st. The tradition, it turns out, is not as timeless as the celebrations themselves and stems from a political crisis in the Roman Republic.
The March Beginning and the Missing Months
In a recent discussion highlighted on social media, science communicator Michael Stevens of Vsauce and mathematician Professor Hannah Fry explored the origins of our calendar. Professor Fry revealed that the Roman year originally commenced in March, aligning with the start of spring. The early Roman calendar spanned just ten months, from March to December.
This historical fact explains the numerical confusion in several month names. September, October, November, and December contain the Latin prefixes for seven, eight, nine, and ten, yet now occupy the ninth through twelfth positions. This is because they were once the seventh through tenth months.
Initially, the period we know as January and February was simply a nameless winter gap of around 60 days, not formally counted on the calendar. With agricultural activity halted, there was deemed little need to track the time. Around 713 BC, the Romans began to account for these days, forming the two new months, but the new year still sprang from March.
The Spanish Revolt That Changed Time
The pivotal shift occurred in 153 BC, as Professor Fry explained, driven by military necessity. "It's all kicking off in Spain," she said, describing a revolt. The Romans needed to appoint two new consuls—the officials who commanded the army—but their rules stated this could only happen at the start of the year, which was March 1st.
Faced with an urgent crisis and unwilling to wait months, the Roman solution was characteristically direct. Rather than change the rule, they changed the beginning of the year. They moved the start date to January 1st, which allowed for the immediate appointment of consuls to handle the Spanish emergency. This administrative decision permanently reset the calendar's starting point.
Months, Myths, and Measuring Winter
A common misconception holds that July and August were added to the calendar. In reality, the months existed as Quintilis and Sextilis (the fifth and sixth months) and were later renamed to honour Julius Caesar and Augustus. The calendar's structure was already in place.
This history raises a practical question: how did people reference dates during the unnamed winter? Experts note that if necessary, days were counted backwards from the "Kalends of March" (March 1st). For instance, the festival of Terminalia, celebrated on what is now February 23rd, was known as "VI. Kal. Mart."—the sixth day before the Kalends of March.
As Professor Fry summarised, the change was a bureaucratic fix for a pressing problem. So, when you raise a glass at midnight tonight, you're participating in a tradition born from an ancient Roman political and military manoeuvre, a testament to how human affairs have always shaped the way we mark time.
