Timeline

This is a comprehensive list of the timeline of known dates of events within the Chainsaw Man universe.

Overview
The Chainsaw Man universe's timeline diverges from our timeline and features apparent anachronisms (e.g. the Soviet Union still exists in 1997 whereas in reality, it collapsed in 1991) due to the abilities of certain Devils.

Time Immemorial

 * Devils emerge in Hell. All Devils are born with a "name" that correlates to a concept. As Devils primarily rely on fear from humanity, it can be inferred that Devils (especially the Primal Devils) emerged roughly the same time.

1940s

 * Kishibe is born.

1945

 * World War II ends and the beginning of the Cold War between the Soviet Union and the United States. World War II spawns a Devil which was later eaten by the Chainsaw Devil. (It can also be inferred that nuclear weapons were developed and deployed as a Nuclear Weapons Devil existed before being eaten by the Chainsaw Devil).

1970s

 * Aki Hayakawa is born.

1975

 * Hirokazu Arai is born.

1977

 * Kobeni Higashiyama is born.

1980s

 * Asa Mitaka is born.

1980

 * Denji is born.

1984

 * November 10 - A large terrorist attack involving guns occurred in the United States, causing that to be the day that the Gun Devil first appeared. The Gun Devil hit several countries around the world in succession eventually leading a death toll of 1.2 million lives in only five minutes, including Japan for 26 seconds, killing 57,912 people.
 * According to Makima, the Soviet Army found the unconscious Gun Devil in the Soviet Union and later its body is separated into several pieces and held by countries and devils. Specifically, 20% of his body is owned by the United States, 28% is owned by the Soviet Union, 11% is owned by China, 4% is owned by other nations and the remaining 37% is in the form of pieces of meat in the hands of devils scattered around the world.

1994

 * Aki joins the Public Safety Devil Hunters and is partnered up with Himeno.

1997

 * The plot of Chainsaw Man begins.
 * September 12 - The American president applied their contract with the American portion of the Gun Devil to attack Makima by sacrificing one year from each American citizen because other countries already gave up fighting her.

199X

 * January - The plot of the Academy Saga begins. It's quickly followed by a 3 month time skip.
 * March - The Falling Devil is summoned and hits Japan killing at least 2,000 people. Mass death also occurs globally.

1999

 * July - Nostradamus's prophecy predicts the end of humanity and takeover for Devils.

2000s

 * End of the 20th century and beginning of the 21st century.

Trivia
At this moment it's uncertain which year the Academy Saga takes place in. There are contradictory hints through the part such as the calendars in the backgrounds of Chapters 119 & 135.