Emperor Taishō (大正天皇, Taishō-tennō^?, 31 August 1879 – 25 December 1926) was the 123rd Emperor of Japan, according to the traditional order of succession, reigning from 30 July 1912 until his death in 1926.

The Emperor's personal name was Yoshihito (嘉仁^?). According to Japanese custom, during the reign the emperor is called the (present) Emperor. After death he is known by a posthumous name that, according to a practice dating to 1912, is the name of the era coinciding with his reign. Having ruled during the Taishō period, he is posthumously known as "The Taishō Emperor" or simply "Emperor Taishō".

Prince Yoshihito was born at the Akasaka Palace in Tokyo to Emperor Meiji and Yanagihara Naruko, a concubine with the official title of gon-no-tenji ("lady of the bedchamber"). As was common practice at the time, Emperor Meiji's consort, Empress Shōken, was officially regarded as his mother. He received the personal name of Yoshihito Shinnō and the title Haru-no-miya from the emperor on 6 September 1879. His two older siblings had died in infancy, and he too was born sickly.

Prince Yoshihito contracted cerebral meningitis within three weeks of his birth, leaving him in poor health. (It has also been rumoured that he suffered from lead poisoning, supposedly contracted from the lead-based makeup his wet nurse used.)

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