Short answers, pulled from the story.
Manchukuo was a puppet state of the Empire of Japan in Manchuria that existed from 1932 until its dissolution in 1945. Although it was nominally a republic and later an empire, Japanese officials made all decisions, and the commander-in-chief of the Kwantung Army could even veto the emperor.
Puyi, the last emperor of China, served as the head of state of Manchukuo. He became chief executive on the 18th of February 1932 and was proclaimed emperor under the era name Kangde when the state became a monarchy on the 1st of March 1934, but he was a figurehead with no real political power.
Manchukuo was proclaimed on the 18th of February 1932 by the Northeast Supreme Administrative Council and formally established on the 1st of March 1932 in Xinjing. It followed the 1931 Mukden incident and the Japanese invasion of Manchuria.
The capital of Manchukuo was Xinjing, the renamed city of Changchun. Manchukuo received formal recognition from Japan on the 15th of September 1932 through the Japan-Manchukuo Protocol.
Manchukuo was toppled when the Soviet Union declared war on Japan on the 8th of August 1945 and invaded the region. Puyi abdicated on the 17th of August, the government was formally dissolved after Japan's surrender in September 1945, and the territory passed to Chinese administration the following year.
Unit 731 was a secret biological and chemical warfare unit operated by the Kwantung Army at Pinfang in Manchukuo. Its doctors performed gruesome experiments on people, and when they demanded European subjects to test anthrax and plague strains, many Russians living in Manchukuo were kidnapped and used as human subjects.
The wangdao, or Kingly Way, was the official ideology of Manchukuo, devised by prime minister Zheng Xiaoxu. It called for an ordered Confucian society and was expressly hostile toward individualism, holding that subjects must put their duties to the emperor and the state ahead of their own needs.