As far as I know, the historical prototypes of the characters in "Bungou Stray Dogs" are these people. Osamu Dazai, a suicide enthusiast, committed suicide five times in his life, and finally drowned in the river in Yukawa, Tokyo, together with the female readers he admired, ending his short and contradictory life. Osamu Dazai was born into a typical wealthy second-generation landowner family, but he never enjoyed any of the benefits that wealth and power brought. He longed for literature all his life, but he drank too much and died of love. His famous masterpieces include: "Human Disqualification", "Clown Flower", etc.
In the anime, Ryunosuke Akutagawa tried his best to gain the approval of Osamu Dazai, but in the real Japanese literary world, it was just the opposite. Ryunosuke Akutagawa committed suicide when Osamu Dazai was only 19 years old. Osamu regarded Ryunosuke Akutagawa as his lifelong idol. His representative works include: "Rashomon", "In the Bamboo Forest", "The Nose", etc. Nakahara Nakaya was the most dazzling star poet in the poetry world of the Showa era. The Japanese literary world was named after the Japanese blue treasure, Nakahara Chuya. Although Chua Nakahara in the comics is short, he has amazing strength and can manipulate gravity, but dirty is what he really looks like. The words he said before taking the stage came from the poems "Goat Song" and "In Dirty Sorrow" by Seiji Nakahara respectively.
Atsushi Nakajima is a famous Japanese novelist, poet, philosopher and moralist. His grandfather and father were both Han Confucians, so he was educated since he was a child. In the manga, Atsushi Nakajima's Monster Under the Moon comes from "Sangetsuki". Mori Ogai is a representative figure of romantic literature after the Meiji Restoration. Together with Natsume Soseki and Akutagawa Ryunosuke, he is known as the three major writers of modern Japanese literature. He also has multiple identities, such as doctor, novelist, critic and translator.
Fukuzawa Yukichi is a famous enlightenment thinker in modern Japan, an outstanding educator in the Meiji period, and the founder of Keio University in Japan. He is known as the father of modern Japanese education. Fukuzawa Yukichi's animation ability is named: People are not created by people, which comes from the work "Encouraging Learning". So as far as I know, the historical prototypes of the characters in "Bungou Stray Dogs" are these people.