Japanese occupation of Hainan

Hainan Island Operation
Part of the Second Sino-Japanese War
Imperial Japanese Army soldiers in trucks during the invasion of Hainan (Asahi Shinbun newsphoto)
Date February 1939 Location Hainan, China Result Japanese victory
Belligerents
Japan	China
Commanders and leaders
Vice Adm. Kondo Nobutake	Yu Hanmou
Units involved
Imperial Japanese Navy	National Revolutionary Army
Strength
Elements of IJN 5th Fleet	25,000
Casualties and losses
Unknown	Unknown

The Hainan Island Operation, or Kainan-tō sakusen (海南島作戦) in Japanese, was part of a campaign by the Empire of Japan during the Second Sino-Japanese War to blockade the Republic of China and prevent it from communicating with the outside world as well as to prevent imports of much-needed arms and materials.

Hainan Island lies midway between French Indochina and Hong Kong, occupying a position south of the Leizhou Peninsula across the Strait of Hainan. It is also near Kwangchowan, a French-leased territory on the southern coast of China. The 33,920 km2 (13,100 sq mi) Hainan Island had a population of 2,200,000 at the time. The island was guarded by the 152nd Division, approximately 25,000 strong, under the command of Yu Hanmou, who was in charge of peace preservation in Kwangtung Province.

The Japanese Navy, after the capture of Canton (Guangzhou) the previous year, had maintained a formidable blockade all along the coast of south, central and north China. However, loopholes were found in the southern end of the blockade line. These included the supply route to Chiang Kai-shek with Hong Kong and Northern French Indo-China as relay points and the direct routes though Hainan Island and Kwangchowan areas. Because of these loopholes, as well as the necessity to conduct air operations deep into the interior as far as the Kunming area, the Japanese Navy came to feel the necessity for establishing air bases on Hainan Island. The Central Authorities of the Navy advocated this move. Operations were carried out by the Special Naval Landing Forces with Army elements supporting them.

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