1915 in Japan

Incumbents

• Emperor: Taishō
• Prime Minister: Ōkuma Shigenobu

  Events

• January 18 - Twenty-One Demands from Japan to China are made.
• March unknown date - A tool brand, Makita founded, as predecessor name was Makita Electronics Manufacturing.
• March 25 - 1915 Japanese general election: The Rikken Dōshikai party emerged as the largest party in the House of Representatives, winning 153 of the 381 seats. The 381 members of the House of Representatives were elected in 51 multi-member constituencies based on prefectures and cities. Voting was restricted to men aged over 25 who paid at least 10 yen a year in direct taxation.
• April 15 - Sato Pharmaceutical was founded.
• May 18 - Toshiko, Princess Yasu, ninth daughter of Emperor Meiji, marries Prince Naruhiko Higashikuni
• September 1 - Yokogawa Electric was founded.
• November 10 - Enthronement of Taishō as the Emperor of Japan in the Imperial Palace in Kyoto. Originally scheduled to be held in 1914, it was postponed for one year in April of the same year due to the death of Empress Shōken.
• November Unknown date - Azuma Kogyo, as predecessor of Teijin, founded in Yonezawa, Yamagata Prefecture.
• December 9-14 - Sankebetsu brown bear incident: was the worst bear attack in Japanese history, killing seven settlers in Rokusensawa, Sankebetsu, Tomamae, Rumoi, Hokkaidō, Japan.
• Ōura scandal
• Tapani incident
• Ongoing - Japan during World War I

  Births

• January 4 - Michiko Kuwano, actress
• January 20 - Masanori Yusa, freestyle swimmer
• February 15 - Haruo Umezaki, writer
• February 20 - Takiko Mizunoe, actress, film producer, and radio and TV presenter
• February 28 - Nobuo Kojima, writer and author
• May 15 - Shozo Makino, swimmer
• October 17 - Taiji Tonoyama, actor
• November 20 - Kon Ichikawa, film director
• December 2 - Takahito, Prince Mikasa, youngest son of Emperor Taishō
• December 25 - Yumeko Aizome, actress

  Deaths

• January 12 - Arisaka Nariakira, Lieutenant general and inventor of the Arisaka rifle
• August 5 - Sakuma Samata, politician and Governor of Taiwan
• September 1 - Inoue Kaoru, politician
• September 4 - Goseda Yoshimatsu, artist
• September 26 - Tsuruko Haraguchi, psychologist and the first Japanese woman to receive a Doctor of Philosophy
• September 28 - Saitō Hajime, samurai of the late Edo period, captain of the third unit of the Shinsengumi
• November 28 - Kobayashi Kiyochika, ukiyo-e artist