World

World (世界, Sekai), also known as Human World or Earth is where humans reside.

Overview
The world is originally home to humans, devils which have been killed in Hell, fiends which are human corpses possessed by devils and hybrids which are humans with the ability to take the form of a devil. Prominent area of the world is Japan where Denji is living.

Japan
Japan is one the countries in the world and the main setting of the series. Its official language is Japanese. It is governed by a Prime Minister who had a contract with Makima. In exchange for working for Japan, any fatal damage inflicted on Makima is transferred to a random citizen of Japan. Public Safety Devil Hunters is working for the government of Japan. The higher-ups for Public Safety Devil Hunters are located in Kyoto, who are also in charge of Makima and her divisions.

In November 10, 1984 the Gun Devil hit Japan for 26 seconds killing 57,912 people. Aki Hayakawa witnessed the Gun Devil destroying his house and killing his family as it passed by.

In September 12, 1997 the Gun Devil appears again at the coast of Kaho City in Akita Prefecture for 12 seconds and killed several men, women and children. However, he is defeated by Makima and then he possessed the corpse of Aki. He is later defeated by Denji. After the defeat of Gun Devil, the Public Safety has formed Anti-Makima Squad to incapacitate Makima, however, they have been failed. Later, Denji defeated Makima by poisoning her blood and eating her piece by piece which allows him to bypass the contract of her and Prime Minister.

After the defeat of the Gun Devil and Makima, Chainsaw Man became a popular hero nationwide who fights against devils. However, his identity is incognito and not known by the public.

United States of America
The United States of America, shortly known as America is one of the countries in the world. Its official language is English. It is governed by a President who had a contract with Gun Devil.

In November 10, 1984 a large terrorist attack involving guns occurred in America, causing that to be the day that the Gun Devil first appeared. The Gun Devil hit America for 124 seconds killing 548,012 people. Aldo, Joey and their brother survived the Gun Devil's attack but lost their home along with their father, mother and grandmother which led them to believe they are immortal. After the defeat of the Gun Devil, America obtained twenty percent of its body.

In September 12, 1997 the President of the United States applied their contract with the Gun Devil (twenty percent) to attack Makima by sacrificing one year from each citizen of the country because other countries already given up to fight against her. However, this resulted into defeat of the Gun Devil that America possesses.

Soviet Union
The Soviet Union, also known as USSR is one of the countries in the world. Its official language is Russian. It presumably governed by President of the Union.

In November 10, 1984 the Gun Devil hit the Soviet Union for 210 seconds killing 155,302 people. Later, The Soviet Union confirmed that the Gun Devil has been defeated by someone else and obtained twenty-eight percent of the its body.

At some point of time, the Soviet Union have taken many children and placed in a special government program to make super-soldiers dedicated to the country. In this program children were subjected to harsh military training and scientific experiments to amplify their natural abilities. A portion of the Bomb Devil's body was placed inside one of the children, thus turning her into a devil-human hybrid. This occurrence was spread through world by an American journalist.

Tolka and his master are also from the Soviet Union, the latter one is the true identity of "Santa Claus" who has a contract with several Devils such as Hell Devil and Doll Devil.

China
China is one of the countries in the world. Its official language is Chinese. It is governed by General.

In November 10, 1984 the Gun Devil hit China for 32 seconds killing 316,932 people. After the defeat of the Gun Devil, China obtained eleven percent of the its body.

Quanxi, who is a hybrid and known as the First Devil Hunter, and her harem of fiends are also from China and work for the General.

After Makima has been defeated by Denji, the Control Devil has reincarnated in China as Nayuta which later found by Kishibe and brought to Japan to live in care of Denji.

Germany
Germany is one of the countries in the world. Its official language is German. Its governmental constitution details are unknown or even if it is unified, however a government agent has been seen to hire a devil hunter. At some point of time, Nazi movement controlled Germany which led to World War II and the Holocaust. However, these all have ceased to exist because of Chainsaw Man's ability to erase things from existence.

One of the perfect dolls of Santa Claus resides in Munich as a famed devil hunter with an alias of "Santa Claus of Germany" which is hired by Germany to kill Makima. According to Makima, Germany holds several Devils under their arsenal.

Other Mentioned Countries

 * Canada - In November 10, 1984 the Gun Devil hit there for 7 seconds killing 8,481 people.
 * India - In November 10, 1984 the Gun Devil hit there for 15 seconds killing 29,950 people.
 * Mexico - In November 10, 1984 the Gun Devil hit there for 2 seconds killing 6,088 people.
 * Hawaii - In November 10, 1984 the Gun Devil hit there for 0.4 seconds killing 780 people.
 * Other countries besides the United States of America, the Soviet Union and China have four percent of the Gun Devil's body. However, these countries and their percent of body ownership is not mentioned.

Trivia

 * In the panel where a street from USA is seen, there is a billboard of Agni who is the titular protagonist of the Fire Punch which is also created by Tatsuki Fujimoto.
 * In the world of Chainsaw Man, the following never happened or ceased to exist: Nazi, World War II, dissolution of the Soviet Union, AIDS and nuclear weapons.
 * In the real world, the USSR collapsed in 1991, but in Chainsaw Man it still exists in 1997. This may be a result of the changes the Chainsaw Devil made to history.
 * It is implied that Hawaii may be a nation of its own, rather than being part of the U.S.A.
 * In the world of Chainsaw man, the following existed or happened but now do not: Mount Hio eruption, Arnolone syndrome, Soa, the sixth sense, the light of particular star that would break children's mind, four other possible conclusions other than death at the end of a living being's life span and the name of human/devil hybrids.