Julian calendar goes into effect (46 BCE)
Julian calendar goes into effect took place in 46 BCE, during the Ancient World (1st century BCE) — a moment that historians still return to for what it changed and what it revealed about its time.
Context
Ancient World — Empires, philosophers, and the first great cities. That's around 2016 years ago — deep history, roughly 20 centuries in the past. Around the same time, the world was also seeing Julian calendar goes into effect by decree of Julius Caesar (46 BCE) and Julian calendar year 1 lasts 445 days to correct erroneous old Roman calendar (46 BCE).
Why it matters
Julian calendar goes into effect is remembered because its consequences outlasted the moment — the people affected, the decisions it forced, and the way it reset the story of what came next.
Did you know?
Just 0 years after, Julian calendar goes into effect by decree of Julius Caesar (46 BCE) was also making headlines — a reminder how much history can compress into a single decade.
Era
Ancient World
Empires, philosophers, and the first great cities.
Category
Events
Events tell the story of moments that reshaped daily life — disasters, revolutions, discoveries, and turning points that split history into before and after.
Contemporary events
What else was happening in the world around this time.
Sources & further reading7 verified references · tap to open
About this lesson. Overview, context, and “Why it matters” are generated summaries written for study and gameplay. Dates and category placement come from the Timeline question bank[1]; era descriptions are adapted from standard historical periodisation[2]. For primary sources and in-depth reading, use the references below.
- Timeline question bank — © the game's original author, used with permission.
- Era framework based on Wikipedia's Human history overview, CC BY-SA 4.0.
Wikipedia
Community-maintained encyclopedia entry with citations.
Encyclopædia Britannica
Editorially reviewed reference articles.
Library of Congress
Primary sources, photographs, and archival records.
National Archives
Original U.S. government documents and records.
Smithsonian
Museum collections and curator-written explainers.
BBC History
Long-form explainers and documentaries.
History.com
Timelines and topic overviews from HISTORY.
Educational content notice
Lessons are for general historical education, not professional advice. Some entries touch on wars, violence, or other sensitive events — appropriate for ages 9+. External links open in your browser and are not controlled by Timeline.
Quick check
Which of these happened in 46 BCE?
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