In the Great Orient, lies the continent called Rodenius.

One day, an unidentified flying object arrived at Qua-Toyne Principality’s airspace. The unidentified flying object defied the Principality’s common sense. But that unidentified flying object was just a harbinger of something even more shocking.

Far to the eastern sea, a group of islands suddenly appeared. The country of the islands called itself: Japan. According to them, their nation had been transported to another world.

Now finding themselves separated from their old world and must survive in the new one, how will Japan interact with the native countries of this world? Will they greet her as a friend or as an enemy?

This is a story of the country called Japan as it was engulfed in the chaotic storm of the world.

Basically, the Japanese version of Island in the Sea of Time. For clarity: The summoned area of Japan are the four disputed Kuril Islands, Japan Home Islands, and Ryuku Islands.

From MangaHelpers:
People have been created that are human-animal hybrids, and powerful businesses bet on the outcome of their duels. College student Nomoto Yuuya's casual acquaintances ask him to drive them around to pick up girls one day, which he soon finds out means by force. The girl they kidnap is an animal-human hybrid named Hitomi, who slaughters all of them except Yuuya. Hitomi is a honey badger, which has been called the most fearless of all animals. Now Hitomi is assigned to stay with Yuuya, for his protection.

In the era of space exploration. Mankind is at war against monsters of unknown origin. The battle is grim, and the future looks bleak. Amidst the chaos, mankind plays their last hand; it's time for the Knights to step into the fray and turn the tide of this war.

The protagonist, Masaru, has just inherited a big fortune after the death of his father. However, people are trying to get their hands on it by any means necessary, even if it means killing him. Narumi helped Masaru from being kidnapped after fighting some weird guys. He found out that they're not humans but wooden puppets with amazing strength. After a hard fight, Narumi was forced to admit that he's no opponent for them; and just when he started to think that Masaru would be captured, Shirogane, Masaru's watcher arrives from France with a weapon, the puppet Arlequin. Here, begins the story of Karakuri Circus.

From: Easy Going Scans
There are gamblers out there who even bet their lives as ante. But to secure the integrity of these life-threatening gambles, a violent and powerful organization by the name of “Kagerou” referees these games as a neutral party. Follow Baku Madarame a.k.a. Usogui (The Lie Eater) as he gambles against maniacal opponents at games – such as Escape the Abandoned Building, Old Maid, and Hangman.

17-year-old Iguchi Tatsuya has just been released from juvenile detention and is on probation. He's been relocated to a new area, away from the bad influence of his old friends, and is under the care of his aunt. He is determined not to be sent back to lockup, and he works hard in his aunt's restaurant. However, he still has the same personality, the same tendency to violence, and still falls in with the same sort of people. It's going to be difficult for him to stay out of trouble

During the political upheavals and social strife at the end of the Tokugawa Shogunate in Japan (1855), two parent-less brothers Yukimura Shoutarou and Yukimura Gentarou struggle to survive in these turbulent times. With their only possession being their deceased father's sword and clinging onto the wisdom of their mother's final words, the brothers seek to embark on the Path of the Warrior: Sidooh.

Azumi focuses upon the life of the titular young female assassin. The manga begins an indeterminate number of years after the Battle of Sekigahara.
As Azumi begins her duty, the manga introduces its characters into mainstream history. Many of the early missions that Azumi undertakes are the assassinations of the prominent supporters and generals of the Toyotomi Clan, against whom Tokugawa Ieyasu expected to again go to war. The manga 'reveals' that many of the Toyotomi leaders who conveniently died of diseases or accidents prior to the final confrontation between the Toyotomi and Tokugawa were actually victims of assassinations by Azumi and her comrades, thus indicating to the reader when the events were taking place.

Note: Won an Excellence Prize at the 1997 Japan Media Arts Festival and the Shogakukan Manga Award in 1998.

In a world entirely ruled by giants, the human race, which has turned into their food, has surrounded its residential zones with immense walls, which both prevent their freedom outside the walls and protect them from incursions. However, as a result of the appearance of supergiants who cross the wall, a desperate struggle begins and the young heroes, who have lost their parents, fight the giant as a training corps, with a view to regaining their freedom.

Note: Won the Kodansha Manga Award in the shōnen category in 2011, was nominated for the 4th annual Manga Taishō award and also for the the 16th and 18th annual Tezuka Osamu Cultural Prize.

Continuation of Kamen Rider Spirits after the series changed magazines, Shin Kamen Rider Spirits follows the war between the evil Badan Empire and the 10 Showa Kamen Riders and their allies.

Senya is just an ordinary guy, who wanted to become an astronaut as a kid. One day and suddenly, he's transported into another world after seeing on the rooftop of his school something like a "tower" going across the sky. There, he witnesses a ruined world, where skyscrapers are connected by suspension bridges. Senya, perplexed, manages to see a girl standing on the roof of another building, as well as a masked man holding a bloody weapon in his hands...

Oomugi Wakaba inherits a mansion from her late great-grandmother, an expert pen artist. Within a hidden room, she meets the mysterious blue-eyed girl wrapped in crimson chains, Red Riding Hood. Together with the strongest beast, she comes to learn about the world of magic, witches and grimoires.

This is the story of a young slave gladiator in an underground arena. He doesn’t know about his past or how he got to where he is, only that his name is Aegir, and that he is strong.

One day he kills the boss and escapes the arena, joining a band of mercenaries as a new recruit. During one mission, they encounter the vampire, Lucy, who slaughters the band with her inhuman strength. After learning that Aegir only knows how to kill, Lucy lets him stay at her house, educating and taking care of him.

Two years pass, and on the day of Aegir’s departure, they both exchange a promise that if Aegir becomes a king and owns the land of Erg forest, he can come and take her as his woman. Making this his life goal, Aegir set out on a journey to become a hero, a king, and found his own kingdom.

From Exertus Scans:
Millions of years have passed since the times of legends, when the worlds of man and gods were still the same. In these times it was the desires of man that moved the world. It is the era of the 500 year war: The warring states period. Kingdom is the story of a young boy named Shin who grew into a great general and all the trials and bloodshed that lead him there.

Note: Kingdom won the grand prize for the Tezuka Osamu Cultural Prize in 2013.
The manga also earned a Guinness World Record on December 12, 2012 for Manga written by the most people. The record was due to its "Social Kingdom" campaign in which fans and other artists were given the task of redrawing the entire 26th volume.

The story drags us into the daily life of Mashiro, a handywoman, who takes care of helping the people of the village. One day, the Dominantor Empire invades the region and captures all the women to make them their slaves. When her friend dies before her eyes, Mashiro, mad with anger, manages to wake up the millennial robot who was secretly residing in the village. It is now her chance to stop the thirst for uncontrollable power of the Dominator Empire. Soon, she is joined by other mecha pilots in this crazy quest to oppose an entire Empire.

On his way home from his office, the main protagonist drove and ran over a big dog. At that moment, he heard the sudden sound of a voice inside his head. ≪ The monster has been subjugated, gaining experience points. ≫ 「Eh?」 Before anyone knew, the world has changed. Monsters appear, this is a game-like world where levels, skills, and status exist. This is an adventure where the modern world becomes fantasy and where the main protagonist has to strive hard for his survival.

A story of a young man who lacks a sense of reality after being dumped by his lover. He was visiting a seminar on cultural anthropology with his fellow classmates when he discoveres an ancient wall painting, which transports him to the past where mammoths dominated the world.Action

There's a new hero in town and he's got a bad attitude and a chainsaw dog demon! A dangerous combo.

In the decade since the world became aware of the existence of magic, the world has undergone massive upheaval. However, a boy named Touta lives in seclusion in a rural town far removed from these changes. His ordinary life is highlighted by his magic-using female teacher and his supportive friends. When his tranquil daily life is disrupted, he embarks on a unique adventure.

After more than 2,000 years, Nomi no Sukune's successor is born. This time, Baki will challenge the god of sumo.