THE HISTORY OF BATTLES OF IMPERIAL JAPANESE ARTILLERY FORCES

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Port Arthur

Date : June, 1904 - Jan., 1905
Place : Port Arthur, China
Opponent : Russian Army

Artillery	Numbers of Gun	Numbers of Fire
10.5cm Cannon	4	2,525
15cm Howitzer	16	11,080
12cm Howizer	28	18,425
12cm Cannon	30	42,040
15cm Mortar	72	30,490
9cm Mortar	24	21,886
28cm Howitzer	18	16,940
Field Gun	120	67,640
Mountain Gun	84	44,100
47mm Gun	14	19,180
Naval Gun	33	78,760
Total	443	353,066

In the Russo-Japanese War, Japan first made war with a western country. The Russian built strong fortifications at Port Arthur and the Japanese struggled to occupy it for a half year. The Japanese artillery forces consumed huge ammunition. In those days, the bombardment was inaccurate and the power of the shell was insufficient against the fortification constructions. The Japanese was much troubled with a supply of ammunition. As the production of the ammunition in Japan was not enough, Japanese imported many ammunition from western countries.

To break the deadlock of the siege, the Japanese sent 28cm Howitzers to Port Arthur. They were effective to destroy the Russian fortifications and much contributed to the occupation of Port Arthur. After the war, Japanese coastal guns were designed for the use in both coast and field.

Xiushui River

Date : March, 1939
Place : Nanchang, China
Opponent : Chinese Army

Artillery Unit		Commander	Artillery
6th Field Heavy Artillery Brigade HQ		Major Gen. Sumita
	13th Field Heavy Artillery Regiment	Lt. Col. Okoshi	24 Type 4 15cm Howitzers
	14th Field Heavy Artillery Regiment	Lt. Col. Maruyama	24 Type 4 15cm Howitzers
	10th Field Heavy Artillery Regiment	Lt. Col. Nagaya	24 Type 4 15cm Howitzers
	15th Independent Field Heavy Artillery Regiment	Col. Horikawa	16 Type 14 10cm Cannons
	2nd Independent Heavy Artillery Battalion	Lt. Col. Manba	4 Type 89 15cm Cannons
101st Field Artillery Regiment		Lt. Col. Yamada	34 Type 38-improved 75mm Field Guns
3rd Independent Mountain Gun Regiment		Lt. Col. Morikawa	24 Type 41 75mm Mountain Guns
106th Field Artillery Regiment		Lt. Col. Uga	32 Type 38-improved 75mm Field Guns
2nd Battalion/2nd Independent Mountain Gun Regiment		Major Matsumoto	12 Type 41 75mm Mountain Guns

During the Sino-Japanese War, Japanese artillery forces marched a long distance in the vast China Continent and they were much troubled with bad roads in China. To lighten the burden to transport the artillery, many artillery regiments replaced their artillery with mountain guns.

Most fights in China were the pursuit battle and the large artillery battle seldom happened. In the Battle of Nanchang, the Japanese deployed the largest artillery forces during the Sino-Japanese War. They bombarded to support the river-crossing of the Japanese at Xiushui River. However, the Chinese little resisted the Japanese river-crossing and the artillery forces stopped bombarding at one third of the plan.

The Nomonhan Incident

Date : June-Aug., 1939
Place : Nomonhan, Manchuria
Opponent : Soviet Army

Artillery Unit		Commander	Artillery
13th Field Artillery Regiment		Col. Ise	24 Type 38 75mm Field Guns 12 Type 38 12cm Howitzers
3rd Field Heavy Artillery Brigade HQ		Major Gen. Hata
	1st Field Heavy Artillery Regiment	Col. Mishima	16 Type 96 15cm Howitzers
	7th Independent Field Heavy Artillery Regiment	Col. Takatsukasa	16 Type 92 10cm Cannons
	Muling Heavy Artillery Regiment	Lt. Col. Someya	6 Type 89 15cm Cannon
	1st Independent Field Artillery Regiment	Col. Miyao	8 Type 90 75mm Field Guns

In the Nomonhan Incident, Japanese artillery forces made an artillery duel against the Soviet. The result was the defeat of the Japanese. Japanese artillery were outranged by the Soviet artillery and the terrain was disadvantagous to the Japanese. However, the most problem was the supply of ammunition again. Japanese artillery forces had used up most of the piled ammunition in three days and they could not continue an artillery duel any more. On the contrary, Soviet artillery continued the heavy bombardment with an abundant supply of ammunition and defeated Japanese artillery.

In the war against the China, the Japanese did not experience large artillery battle. They had forgotten the lesson of the Port Authur. The result of the Nomonhan battle revealed the problems of Japanese artillery forces. However, while they were not improved, Japan was driving to the war in the Pacific.

Bataan and Corregidor

Date : Jan. - May, 1942
Place : The Philippines
Opponent : US Army

Artillery Unit		Commander	Artillery
4th Field Gun Regiment		Col. Inoue	16 Type 38-improved 75mm Field Guns 8 Type 91 10cm Howitzers
22nd Field Gun Regiment		Col. Itoh	24 Type 38-improved 75mm Field Guns 12 Type 91 10cm Howitzers
Field Gun Batteries/65th Brigade			12 Type 38 75mm Field Guns
3rd Battalion/51st Mountain Gun Regiment		Major Arima	12 Type 41 75mm Mountain Guns
1st Artillery HQ		Major Gen. Kitajima
	1st Field Heavy Artillery Regiment	Col. Irie	24 Type 96 15cm Howitzers
	8th Field Heavy Artillery Regiment	Lt. Col. Takahashi	16 Type 92 10cm Cannons
	3rd Independent Mountain Gun Regiment	Lt. Col. Takamori	24 Type 41 75mm Mountain Guns
	1st Heavy Artillery Regiment	Col. Hayakawa	8 Type 45 24cm Howitzers
	9th Independent Heavy Artillery Battalion	Lt. Col. Sugai	8 Type 89 15cm Cannons
	2nd Independent Heavy Artillery Company	Captain Shinoda	2 Type 96 15cm Cannons 2 Type 96 24cm Howitzers
	2nd Independent Mortar Battalion	Lt. Col. Namimatsu	12 15cm Mortars
	14th Independent Mortar Battalion	Major Tanaka	16 Type 98 32cm Spigot Mortars
	15th Independent Mortar Battalion	Lt. Col. Yoshida	8 Type 98 32cm Spigot Mortars

After the failure of the first attack against the Bataan, the Japanese GHQ sent strong artillery forces to the Philippines in order to smash the American fortifications. They had 190 guns and included some big guns like 15cm cannons or 24cm howitzers. Especially, Type 96 24cm Howitzer was a very rare gun and its action is only known in this battle. To command and control these artillery forces, the 1st Artillery HQ also moved to the Philippines. The HQ commander was Major Gen. Kineo Kitajima, who was a leader and authority of the IJA artillery.

On April 3rd, about 300 guns bombarded the enemy positions. It started from 9:00 and continued to 15:00. Synchronized with bombardment, about 100 airplanes dropped more than 700 bombs. The land shaked and the mountains were covered with the dust of explosion. It was just like a volcano erupted. When the Japanese troops started the attack at 15:00, there was a little resistance. American defenders, shocked by heavy bombardment were routed. The Bataan Peninsula was occupied only in one week.

The consumption of the shells during the battle of Bataan is as follows.

Type 41 75mm Mountain Guns - 1,389 rounds
Type 94 75mm Mountain Guns - 6,822 rounds
Type 38-improved 75mm Field Guns - 16,875 rounds
Type 91 10cm Howitzers - 2,908 rounds
Type 92 10cm Cannons - 4,595 rounds
Type 96 15cm Howitzers - 6,300 rounds
Type 89 15cm Cannons - 1,130 rounds
Type 45 24cm Howitzers - 1,047 rounds
Type 96 24cm Howitzers - 80 rounds
Type 98 32cm Spigot Mortars - 175 rounds

In the battle of Corregidor, heavy artillery were used to destroy the batteries on the fortress islands. The Type 96 15cm Cannon first saw action at this time. They bombarded the Corregidor and two islands for about one month and silenced most enemy batteries. On May 5th, Japanese ground forces landed the Corregidor Island and the garrisons surrendered the next day.

The consumption of the shells during the battle of Corregidor is as follows.

Type 92 10cm Cannons - 7,246 rounds
Type 96 15cm Howitzers - 8,793 rounds
Type 89/96 15cm Cannons - 3,513 rounds
Type 45/96 24cm Howitzers - 2,915 rounds

Guadalcanal

Date : Aug., 1942 - Feb., 1943
Place : Guadalcanal
Opponent : US Marine/Army

Artillery Unit	Commander	Artillery
10th Independent Mountain Gun Regiment (3 batteries only)	Lt. Col. Kitayama	9 Type 41 75mm Mountain Guns
20th Independent Mountain Gun Battalion	Lt. Col. Kaji	6 Bofors 75mm Mountain Guns
4th Field Heavy Artillery Regiment	Col. Akamatsu	12 Type 96 15cm Howitzers
2nd Battery/7th Field Heavy Artillery Regiment	1st Lt. Tani	4 Type 92 10cm Cannons
2nd Battery/21st Field Heavy Artillery Battalion	Captain Tanaka	4 Type 4 15cm Howitzers
2nd Field Artillery Regiment	Col. Ishizaki	7 Type 38-improved 75mm Field Guns 4 Type 91 10cm Howitzers 5 Bofors 75mm Mountain Guns
3 Batteries/38th Mountain Gun Regiment		5 Type 41 75mm Mountain Guns 2 Type 94 75mm Mountain Guns

For the October offensive, the Japanese sent some artillery units to Guadalcanal. Sending artillery were almost landed on Guadalcanal, but ammunition were many lost by enemy airraid. During the October offensive, most artillery units were attached to the Sumiyoshi Detachment and deployed in the west bank of the Matanikau River. The ammunition of these units were very few as shown below.

75mm Field Gun - 1,370 rounds
75mm Mountain Gun - 150 rounds
Type 91 10cm Howitzer - Unknown
Type 4 15cm Howitzer - 420 rounds
Type 96 15cm Howitzer - 709 rounds
Type 92 10cm Cannon - 742 rounds

Due to the shortage of the ammunition, the bombardment of Japanese artillery was limited. They could only disturb the enemy. Moreover, once a Japanese artillery fired, the Americans heavily counterattacked it by air and artillery. For fear of American counterattack, Japanese artillery men became to hesitate to fire.

When the Japanese evacuated Guadalcanal, one 15cm howitzer continued to fire to the end in order to camouflage the Japanese evacuation. It was the last artillery of the Japanese on Guadalcanal.

Saipan

Date : June, 1944
Place : Saipan
Opponent : US Army/Marine

Artillery Unit	Commander	Artillery
Artillery Unit/47th Independent Mixed Brigade	Captain Yamane	8 Type 95 75mm Field Guns 14 Type 91 10cm Howitzers
3rd Independent Mountain Gun Regiment	Lt. Col. Nakajima	12 Type 41 75mm Mountain Guns 12 Type 4 15cm Howitzers
Artillery Battalion/135th Infantry Regiment	Major Aikawa	9 Type 38 75mm Field Guns 3 Type 41 75mm Mountain Guns
Artillery Battalion/136th Infantry Regiment	Major Yabuki	9 Type 38 75mm Field Guns 3 Type 41 75mm Mountain Guns
IJN		4 20cm Naval Guns 14 15cm Naval Guns 3 14cm Naval Guns 4 12cm Naval Guns 4 8cm Naval Guns

Despite the heavy bombardment and bombing of the Americans prior to the landing, Japanese artillery were not so damaged because they were well camouflaged. When landing crafts approached the beach, Japanese artillery opened fire and damaged several crafts. Especially, Japanese 15cm Howitzers bombarded the landing beach heavily and shocked American soldiers. The Americans landed their guns and coped with Japanese artillery. By furious artillery duel, about a half of Japanese artillery were destroyed until the evening.

At the night of 16th day, the Japanese made a large counterattack. Japanese artillery supported it and bombarded enemy artillery positions. Japanese infantymen and tanks rushed to the enemy. However, they were replused by the Americans and suffered heavy losses. Japanese artillery were mostly destroyed until the evening of 17th day.

Iwo Jima

Date : Feb. to March, 1945
Place : Iwo Jima, Bonin Islands
Opponent : US Marine

Artillery Unit		Commander	Artillery
2nd Mixed Brigade Artillery Group HQ		Col. Kaido
	Artillery Unit/2nd Mixed Brigade	Major Maeda	10 75mm Field Guns 5 Type 41 75mm Mountain Guns 6 Type 38 12cm Howitzers
	Artillery Battalion/145th Infantry Regiment	Captain Masuda	9 Type 38-improved 75mm Field Guns 4 Type 38 12cm Howitzers
	20th Independent Mortar Battalion	Captain Mizutari	12 Type 98 32cm Spigot Mortars 12-24 Light Infantry Mortars
	2nd Medium Infantry Mortar Battalion	Major Nakao	12 Type 96 150mm Infantry Mortars 12 Light Infantry Mortars
	3rd Medium Infantry Mortar Battalion	Major Kobayashi	10 Type 96 150mm Infantry Mortars 6 Light Infantry Mortars
	Rocket Artillery Company	1st Lt. Yokoyama	40 20cm/40cm Rocket Launchers
1st Independent Infantry Mortar Company		1st Lt. Yamaki	12 Naval Type 3 80cm Infantry Mortars
Artillery Company/26th Tank Regiment		1st Lt. Kishi	8 Type 90 75mm Field Guns
IJN			4 15cm Naval Guns 4 14cm Naval Guns 7 12cm Naval Guns 8 12cm Short Naval Guns

The Japanese garrisons built strong fortifications on Iwo Jima. Artillery were hidden in cave or pillbox and well protected from the bombardment and airraid. In the underground magazines, they had stocked about 60% of the standard ammunition for one campaign. Except for naval guns, there were no heavy artillery. But, they had received some rocket artillery. They were 20cm or 40cm caliber, which are equal to the gun of warship.

The Americans landed on Iwo Jima suffered serious damage by Japanese shellfires. Japanese artillery endured for a long-time fight and supported the resistance of the garrisons. They devoted themselves to the bombardment by surprise and never made an artillery duel. Field guns ambushed and destroyed enemy tanks.

During the battle of Iwo Jima, Americans suffered 6,800 killed and more than 19,000 wounded. Most of them were caused by the bombardment of artillery and mortar. In the 4th Marine Division, for example, 75% of the casualties were due to the bombardment. Japanese artillery forces on Iwo Jima had accomplished their duty.

Kotou Fortess

Date : Aug., 1945
Place : Manchuria
Opponent : Soviet Army

Artillery Unit/15th Border Guard Unit (Captain Ohki)
	1st Battery	1 Experimental 41cm Howitzer 2 Type 7 30cm Long Howitzers 2 Type 45 24cm Howitzers
	2nd Battery	2 Type 96 15cm Cannons 4 Type 45 15cm Cannons 2 Type 38 75mm Field Guns

Kotou Fortress located near Ussuri River in the Soviet-Manchurian border (See map). It was the strongest fortress among eight Japanese fortresses in Manchuria and the 4th Border Guard Unit guarded it. The 4th Border Guard Unit had following artillery unit. 41cm Howitzer was the largest gun of the IJA and Type 90 24cm Railway Gun was only one railway gun of the IJA.

Artillery Unit/4th Border Guard Unit (Feb. 1940)
	1st Battalion	2 Type 7 30cm Long Howitzers, 2 Type 45 24cm Howitzers, 2 Type 96 15cm Cannons, 4 Type 45 15cm Cannons
	2nd Battalion	8 Type 91 10cm Howitzers, 6 Type 90 75mm Field Guns, 2 Type 38 75mm Field Guns
	3rd Battalion	18 Type 88 75mm AA Guns
	13th Battery	Type 90 24cm Railway Gun
	14th Battery	Experimental 41cm Howitzer

As the Japanese declined in the Pacific theater, many soldiers and guns were extracted from the Kotou Fortress and sent to the Pacific. In 1945, the 4th Border Guard Unit was disbanded and the 15th Border Guard Unit was formed in July, 1945 as the garrison unit of the Kotou Fortress.

When the Soviets invaded Manchuria in Aug., 1945, there were about 1,400 garrisons at the fortress. The 41cm gun fired and destroyed a railway bridge of the Trans-Siberian Railroad. Then, it fired with over 100 rounds during about one week until it was overrun by Soviet infantry.

Though the Soviets announced the surrender of Japan, Japanese garrisons did not believe it. They continued to fight until they were annihilated. The battle of Kotou Fortress ended on Aug. 26th.