Hainan Island Operation
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 Indo-China 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 land combat units with Army elements supporting them.
Escorting a convoy, the South China Naval Force (Fifth Fleet) commanded by Vice Admiral Kondo Nobutake entered and anchored in Tsinghai Bay on the northern shore of Hainan Island at midnight on 9 February 1939 and carried out a successful landing. In addition, Navy land combat units affected a landing at Haikou at 1200 on 10 February. Thereafter, the Army and Navy forces acted in concert to mop up the northern zone. On 11 February the land combat units landed at Samah (Sanya) at the southern extremity of Hainan Island and occupied the key positions of Yulin and Yai-Hsien. Thereafter, the units engaged in the occupation and subjugation of the entire island.
The Communists (under Feng Baiju) and the native Li people of Hainan fought a vigorous guerrilla campaign against the Japanese occupation, but in retaliation over one third of the male population were killed by the Japanese.
Later, Hainan Island became a naval administrative district with Hainan Guard District Headquarters established at Samah. Strategically, the island was built as a forward air base as well as an advance base for blockading Chiang. At the same time, the iron and copper resources of the island were exploited.
Control of Hainan Island provided a base of operations for the invasion of Guangdong province and French Indochina, as well as providing airbases that permitted long-distance air raids of routes into China from French Indochina and Burma.
The Occupation of Hainan lasted until the Surrender of Japan in August 1945.
- Japanese Monograph No. 144: POLITICAL STRATEGY PRIOR TO OUTBREAK OF WAR PART I, Prepared by MILITARY HISTORY SECTION HEADQUARTERS, ARMY FORCES FAR EAST, DISTRIBUTED BY OFFICE OF THE CHIEF OF MILITARY HISTORY DEPARTMENT OF THE ARMY, Chapter 4, Operations against China during 1939 Pg 46-47.
- 中国抗日战争正面战场作战记 China's Anti-Japanese War Combat Operations
- Phillips, R. T. "The Japanese Occupation of Hainan," Modern Asian Studies, Vol. 14, No. 1 (1980), pp. 93-109, 
- Hainan Lawyers' group to help ex-'comfort women,' China Daily, 2006-03-23,