A Civilization (文明, Bunmei) is the main chronological term in which the Kadonoverse's timeline is ordered. There are seven currently known civilizations, of which three are almost identical to what humanity has experienced so far.
The First Civilization
The first human civilization in history. It is unknown when exactly this civilization ends, but it presumably starts with the beginning of human society.
The Second Civilization
The second human civilization in history. It is unknown when it begins and when it ends.
The Third Civilization
The third human civilization in history. Known as the "Contemporary Civilization". This is the era of the Towa Organization's rule over the world, and it includes modern times. Although its exact starting point is currently unknown, it is known that the Organization has existed for hundreds of years, and that, at the very least, the end of the 19th century is included, as shown in the short story London Calling, which depicts the defeat of the enemies of the world of that era.
Most works in the Kadonoverse are set in this time. Works set in the Third Civilization:
The Fourth Civilization
The fourth human civilization in history. Known as the "Civilization of Gravity Control and Super Light Speed". Again, exact dates aren't stated, but it's said to take place 5000 to 10000 years after the Third Civilization. This is the age of space exploration and most advanced technology, being the "climax" of humanity in terms of science. It's at this time that humans start fighting with the alien civilization known as the Empty Fangs, utilizing machines known as "Night Watches", as well as the birth of the 'first' Wonder Bearer and protector of mankind, Mylow Starscraper.
Works set in the Fourth Civilization:
The Fifth Civilization
The fifth human civilization in history. Known as the "Civilization of Resourceless Society". An era of confusion, where humanity, defeated by the Empty Fangs, have once again returned to the Earth to try and survive. It is a time filled with endless fighting, where two main factions battle for supremacy for over 1000 years: the Miracle Army, made up of Wonder Bearers, and the Cardinal Army, led by the Cardinal King. Fallen Night Watches that were defeared by the Empty Fangs in the previous era now serve as production plants for materials above ground.
Works set in the Fifth Civilization:
The Sixth Civilization
The sixth human civilization in history. Known as the "Civilization of Large Scale Magic". In this era, the study of the technology known as Magic was elevated, which led to the revival of war through large-scale destruction weapons. ROOROODOO VAY-PER was born during this time. Eurida was created in this era, and was responsible for its destruction, until she was sealed.
Works set in the Sixth Civilization:
The Seventh Civilization
The seventh and final known human civilization in history. Known as the "Civilization of Small Scale Magic". An era of development in Magic control, and the use of Magic as an efficient resource. This era takes place 4300 years after the Fourth Civilization. The biggest human settlement during this time is the Great Empire Gouque, founded by first emperor Gouque and currently ruled by Lawtifeld Lawly Gouque XVII. A fighting robot named JUGHEAD Type-Q, manufactured in the Fourth Civilization, was discovered during this time, and Eurida was awoken by Dr. Vimact Kamming.
Works set in the Seventh Civilization:
Main Article: Interface World
A world separate from the one featured in other works, though the two worlds exist in the same universe, shown by the fact that several things from the "normal world", including books written by Seiichi Kirima, have been transported to the Interface World.