Why the Week Has Exactly 7 Days (And Not 5, 8, or 10)

Why does the week have exactly seven days? It’s not based on the months, the seasons, or even the solar year—so who decided this? Why not a 5-day, 8-day, or 10-day week? And could we change it? In this video, we explore the hidden history of the seven-day week, tracing its origins from Babylonian astronomy to Roman traditions and religious influence. You’ll learn why the Babylonians structured time around seven celestial bodies, why the Romans had eight-day weeks, how the French Revolutionary Calendar failed, and how the moon’s phases might have played a role. By the end, we’ll ask the big question—should we redefine the week? Could a five-day or ten-day system work better in today’s world? Let’s talk in the comments. Timestamps: 0:00 - Why the 7-day week is so strange 0:58 - The Babylonian influence: 7 planets, 7 days 1:45 - Civilizations that used different week lengths 2:35 - How religion reinforced the 7-day cycle 3:10 - Did the moon play a role? 3:45 - Could we change the week to 5 or 10 days? References & Sources: O’Neil, W. M. Time and the Calendars (1975) – Babylonian astronomy and timekeeping Beard, Mary. SPQR: A History of Ancient Rome (2015) – Roman calendar systems Palmer, R. R. Twelve Who Ruled (1941) – The French Revolutionary Calendar Duncan Steel. Marking Time: The Epic Quest to Invent the Perfect Calendar (2001) – Lunar cycles and timekeeping #History #Calendars #Timekeeping #7DayWeek #Why7Days #AncientHistory #ScienceExplained #DeepDive #Educational