Which emperor of the Han Dynasty took the first month as the beginning of a year?

In the history of our country, the first month was formally established in the period of Emperor Wu of Han Dynasty. In the first year of the Western Han Dynasty (BC 104), Emperor Wu of the Han Dynasty accepted the suggestions of Sima Qian and others, adopted the taichu calendar, restored the summer calendar, that is, the lunar calendar, and put the 24 solar terms into the calendar with the first month as a year.

Emperor Wu of the Han Dynasty (Liu Che, BC1July 56 14-March 29, 87 BC), the seventh emperor of the Western Han Dynasty (reigned from BC14/year to the first 87 years). At the age of 16, he ascended the throne, promulgated laws and decrees politically, publicized favouritism and strengthened autocratic monarchy and centralization. Economically, we should implement leveling, even losing money, calculating and warning to curb businessmen. Culturally, hundreds of schools were ousted, Confucianism was the only one, and imperial academy was established.