Former IJA 2nd Division Headquarters Site (Sendai Castle)

The site of the former Imperial Japanese Army 2nd Division Headquarters (陸軍第二師団司令部跡) occupies the ni-no-maru (second bailey) of Sendai Castle (仙台城, also known as Aoba Castle / 青葉城) in Aoba-ku, Sendai City, Miyagi Prefecture. This location represents one of the most historically significant military sites in the Tohoku region — the home base of a division whose soldiers marched from northeastern Japan to battlefields spanning China, Manchuria, the Dutch East Indies, Guadalcanal, and Burma.

From Sendai Garrison to 2nd Division (1871–1888)

Sendai's role as a military center began in 1871 (Meiji 4) when the Tōhoku Garrison (東北鎮台) — later renamed the Sendai Garrison (仙台鎮台, Sendai Chindai) — was established as one of the regional garrisons of the fledgling Imperial Japanese Army. The garrison occupied the ni-no-maru (second bailey) of Sendai Castle, formerly the administrative heart of the Date clan domain during the Edo period. On 14 May 1888 (Meiji 21), as part of the army's reorganization from regional garrisons into a modern divisional structure, the Sendai Garrison was reorganized as the 2nd Division (第二師団). The last garrison commander, Lieutenant General Sakuma Samata, became the first division commander. The division recruited troops primarily from the Tohoku prefectures of Miyagi, Fukushima, and Niigata.

Division Composition and Facilities

The 2nd Division was composed of the 4th Infantry Regiment (歩兵第四聯隊, based in Sendai), the 5th Infantry Regiment (Aomori), the 16th Infantry Regiment (Shibata, Niigata), the 17th Infantry Regiment (Sendai), plus the 2nd Field Artillery Regiment, 2nd Cavalry Battalion, 2nd Engineer Battalion, and 2nd Transport Battalion. The division headquarters occupied the ni-no-maru, while infantry barracks, drill grounds, supply depots, and an army hospital extended throughout the castle grounds and surrounding Kawauchi district. The historic Ōte-mon gate (大手門), a surviving Edo-period structure, served as the main entrance to the military compound.

Early Campaigns (1894–1922)

The 2nd Division served in every major conflict of Imperial Japan's expansion. During the First Sino-Japanese War (1894–95), it landed on the Shandong Peninsula and fought at Weihaiwei, and afterwards took part in the conquest of Taiwan. In the Russo-Japanese War (1904–05), it participated in the battles of Liaoyang and Mukden under the Manchurian front. It was also deployed during the Siberian Intervention (1918–22) to the Russian Far East.

The Pacific War: Dutch East Indies and Guadalcanal (1941–1943)

At the outbreak of the Pacific War, the 2nd Division was initially assigned to the 16th Army for the invasion of the Dutch East Indies (January–March 1942), participating in the rapid conquest of Java. Following the Dutch surrender, the division was transferred to Rabaul on 13 September 1942 and subsequently committed to the Guadalcanal campaign — a decision that would prove devastating.

On 1–5 October 1942, the division landed on the west coast of Guadalcanal near the Matanikau River, immediately suffering over 700 casualties in the Actions along the Matanikau. The division's darkest hour came during the Battle for Henderson Field (24–26 October 1942), when Lieutenant General Maruyama Masao ordered approximately 7,000 troops — organized in three infantry regiments — to march through dense jungle and attack the American-held airfield from the south. The attack was a catastrophic failure: the jungle march took far longer than planned, coordination between units collapsed, and the defenders — primarily the 1st Marine Division and elements of the U.S. Army's Americal Division — repulsed every Japanese assault with devastating firepower. More than 1,500 of Maruyama's troops were killed in the attacks alone, with total Japanese losses reaching 2,200–3,000. The division's overall losses in the Guadalcanal campaign exceeded 7,000 men. The remnants were evacuated in February 1943 during Operation Ke.

Burma and War's End (1943–1945)

After Guadalcanal, the shattered division was rebuilt and reassigned to security duties in the Malaya-Singapore area. From 1944, the division was deployed to Burma, where it participated in defensive operations against the British-Indian advance. The division was withdrawing from Burma and had reached Saigon in French Indochina when the war ended in August 1945.

Destruction of the Headquarters (1945)

Back in Sendai, the castle grounds continued to function as a military command center under the Reserve 2nd Division and the Sendai District Army command (仙台師管区司令部). In the early hours of 10 July 1945, 123 B-29 bombers of the XXI Bomber Command struck Sendai in a devastating firebombing raid, dropping 12,961 incendiary bombs and clusters (911.3 tons) according to U.S. records. The raid destroyed about 23% of the city's built-up area and killed over 1,000 civilians. Within the castle grounds, the conflagration consumed the 2nd Division headquarters buildings, the historic Ōte-mon gate (大手門) — a National Treasure-designated structure dating to the early Edo period — the Wakiyagura corner turret, the Tatsumi-mon gate, the Gokoku Shrine, and virtually all military structures. The loss of the Ōte-mon, one of only a handful of original castle structures to have survived into the modern era, was an irreplaceable blow to Sendai's architectural heritage.

Postwar Occupation and Transformation

Following Japan's surrender in August 1945, the U.S. occupation forces requisitioned the Sendai Castle grounds and established "Camp Sendai" as a military residential facility, which remained in use until 1957. After the Americans departed, the ni-no-maru area — the former 2nd Division headquarters site — was allocated to Tohoku University and developed into the Kawauchi Campus (川内キャンパス), where the university's humanities faculties are now located. Archaeological excavations by Tohoku University have uncovered remnants of both the Edo-period Date clan structures and the Meiji-era military facilities beneath the campus.

The honmaru (main bailey) area of Sendai Castle was developed as Aobayama Park (青葉山公園). The iconic equestrian statue of Date Masamune, originally erected in 1935 and rebuilt in 1964 after the wartime metal collection, stands on the honmaru overlooking the city. The castle's massive stone walls — including the northern honmaru walls stretching 179 meters with a maximum height of 17 meters — remain the most impressive surviving feature and are designated as a National Historic Site.

Today, the Sendai Castle site bears multiple layers of history: the Date clan's feudal legacy, the Imperial Army's modern military transformation, the devastation of wartime air raids, and the postwar rebirth as a university campus and public park. While few visible traces of the 2nd Division headquarters remain, the site's significance as the birthplace of a division that fought — and was nearly destroyed — at Guadalcanal ensures its place in the history of the Pacific War.