Osaka Winter Campaign

In the autumn of Keichō 19 (1614), Tokugawa Ieyasu raised an army to subjugate Toyotomi Hideyori using the "Hōkōji bell inscription incident" as a pretext. This siege, in which armies of approximately 200,000 from east and west encircled Osaka Castle, is called the "Osaka Winter Campaign" and is recorded as one of the largest castle sieges in Japanese history.

The Hōkōji Bell Inscription Incident and the Pretext for War

In Keichō 19 (1614), a large bell cast by the Toyotomi to commemorate the rebuilding of the Great Buddha Hall at Hōkōji in Kyoto bore inscriptions with the characters "Kokka Anko" (National Stability) and "Kunshim Hōraku" (Lord and Vassal's Joy). The Tokugawa side deemed this a curse—"dividing the characters of Ieyasu's name (Ie + Yasu) and bringing joy to the Toyotomi lord and vassals." This interpretation was nearly baseless, but it served as sufficient political pretext for Ieyasu to destroy the Toyotomi.

In the tenth month of that year, Ieyasu's conscription of feudal lords assembled approximately 200,000 troops. Against them, at Hideyori's command, defeated daimyo and ronin from Sekigahara—including Sanada Yukimura, Gotō Mototsugu, Chōsokabe Morichika, and Akashi Takatada—rallied to organize a force of approximately 90,000.

The Defense of Sanada-maru—A Battlefield Where Swords and Cannons Coexisted

The most famous episode of the Osaka Winter Campaign is Sanada Yukimura's (Shigenobu's) construction and defense of the outwork "Sanada-maru."

On the southern side of Osaka Castle—the most vulnerable direction—Yukimura constructed a semicircular redoubt called "Sanada-maru" using wooden palisades and earth embankments. On December 4 (old calendar), Tokugawa vanguard forces led by Maeda Toshitsune and Ii Naotaka advanced on the Sanada-maru, but Yukimura skillfully deployed muskets and bows to repel them. In this battle, Yukimura inflicted severe casualties on the Tokugawa forces and in one stroke made his name resound throughout Japan.

The battle of Sanada-maru clearly demonstrates the mixed warfare style of the late Sengoku period employing swords, spears, and firearms. At close range, swords and spears were used; at distance, firearms and arrows. Under Yukimura's command, these were skillfully combined. Swords of this era served simultaneously as practical weapons in actual combat and as symbolic markers of a general's status and honor.

Cannon Bombardment and Peace Negotiations

Struggling with Osaka Castle's resolute defense, Ieyasu resorted to a shocking measure—bombarding the keep with English culverins imported from Britain, which enabled long-range fire. Shells reportedly fell near the keep, and attendants of Hideyori's mother, Yodo-dono, were killed. This bombardment struck a heavy psychological blow against the Toyotomi.

In mid-December, both sides entered peace negotiations, and an armistice was concluded on December 19 (old calendar). The Toyotomi accepted the filling of both outer and inner moats as terms. However, Ieyasu later expansively reinterpreted this agreement and had nearly all of Hideyori's castle moats filled. This produced a fateful consequence—in the following year's Summer Campaign (Keichō 20), it made a total assault on the now-defenseless Osaka Castle possible.

Toyotomi Generals and Their Swords

The Toyotomi generals in the Osaka Winter Campaign were largely men who had been defeated at Sekigahara and become ronin, and their swords possessed diverse origins from various regions.

Gotō Mototsugu, known as a fierce warrior described as "wielding a great sword with strength," left the Kuroda clan and entered Toyotomi Hideyori's service. While detailed historical records of Mototsugu's blade are sparse, it is suggested that he used swords from Bungo smiths, including the Gotō school.

Chōsokabe Morichika came from the Tosa (present-day Kōchi Prefecture) lineage of an old daimyo house. After his removal from his domain following Sekigahara, he entered Osaka as a ronin. Tosa possessed its own distinctive sword culture, and Morichika is thought to have worn great swords or blades with connections to Tosa.

The Historical Significance of the Winter Campaign

The Osaka Winter Campaign was the first phase in Tokugawa Ieyasu's process of ultimately destroying the Toyotomi. Superficially concluded by armistice, the condition to fill the moats represented a fatal military loss for the Toyotomi.

In the following year's Osaka Summer Campaign, with the defensive strength of Osaka Castle greatly diminished, the Tokugawa forces advanced on the castle more easily. Toyotomi Hideyori and Yodo-dono perished by their own hands within the castle, and the Toyotomi were extinguished.

From the perspective of sword history, the Osaka Winter Campaign was a precursor to "the final stage where Sengoku swords shone brightest." The blades worn by Toyotomi's valiant generals—Sanada Yukimura, Gotō Mototsugu, and others—became swords that curtained the age of swords on the battlefield together with the following year's Summer Campaign. After Edo peace arrived, these swords were collected and preserved as "relics of legendary generals" and passed down as masterpieces in sword culture.