Operation U-Go - Japanese Plans

Japanese Plans

The Allies were preparing to take the offensive themselves in early 1944. The Indian XV Corps was advancing in the coastal Arakan Province, while the British IV Corps had pushed two Indian infantry divisions almost to the Chindwin River at Tamu and Tiddim. These two divisions were widely separated and vulnerable to being isolated.

The Japanese planned that a division from the Twenty-Eighth Army would launch a diversionary attack in the Arakan, codenamed Ha Go, in the first week of February. This would attract Allied reserves from Assam, and also create the impression that the Japanese intended to attack Bengal through Chittagong.

In the centre, Mutaguchi's Fifteenth Army would launch the main attack into Manipur in the first week in March, aiming to capture Imphal and Kohima, scattering British forces and forestalling any offensive movements against Burma. In detail, the Fifteenth Army plans were:

• The Japanese 33rd Infantry Division under Lieutenant-General Motoso Yanagida would destroy the 17th Indian Infantry Division at Tiddim, then attack Imphal from the south.
• Yamamoto Force, formed from units detached from the Japanese 33rd and 15th Divisions under Major-General Tsunoru Yamamoto (commander of 33rd Division's Infantry Group), would destroy the 20th Indian Infantry Division at Tamu, then attack Imphal from the east.
• The Japanese 15th Infantry Division under Lieutenant-General Masafumi Yamauchi would envelop Imphal from the north.
• In a separate subsidiary operation, the Japanese 31st Infantry Division under Lieutenant-General Kōtoku Satō would isolate Imphal by capturing Kohima, then exploit to the vital Allied supply base at Dimapur.

At the insistence of Bose, two brigades from the Indian National Army were also assigned to the attacks on Imphal from the south and east. The Japanese had originally intended using the INA only for reconnaissance and propaganda.

The staff at Burma Area Army had originally thought this plan too risky. They believed it was unwise to separate the attacking forces so widely, but several officers who were vocal in their opposition were transferred. Mutaguchi's divisional commanders were also pessimistic. They thought that Mutaguchi was gambling too heavily on gaining early success to solve supply problems. Some of them thought him a "blockhead", or reckless.