A Drastic Change in Naval Battles

More than 2 decades after the introduction of guns to Japan, Oda Nobunaga (1534-1582) was facing the pressing need to gain naval supremacy in the Seto Inland Sea to fight against the Mori Clan.  Nobunaga heavily lost to navies of the Mori and Kono Clan in the Battle of Kizu-gawa Estuary in July, 1576.  In June and November, 1578, however, he fought against navies of the Mori Clan and the Saika people again, which ended as his overwhelming victory.  We are going to compare the entries about the two naval battles from the Biography of Lord Nobunaga, which was written by Ota Gyuichi (1527-1613), who had been one of the best arrow shooters of Nobunaga when young and who was very good at writing war tales after he became a secretary.

 

“They stopped our ships, and shot many earthenware explosives to burn the ships down.  We were heavily outnumbered, and lost veteran samurais such as Manabe Sadatomo, Numa Iga, Numa Den’nai.  Western forces won a victory in the battle, shipped military provisions into Osaka Hongan-ji Temple, and sailed their forces back to the western provinces.”

 

“On June 26, in the 6th year of Tensho, our ships sailed out to the Sea of Kumano-ura, sailed to Osaka.  They rowed numerous boats out of Soga, Tan’nowa and as such against our big ships off Tan’nowa.  They shot arrows and guns, and pressed attacks on us from all sides.  Kuki Yoshitaka (1542-1600), who had decorated the 7 ships like mountains, fought restrictively first, waited for the enemy boats to come closer, then fired big guns all at once, and destroyed many of the enemy boats.  Afterward, the enemy boats could hardly find ways to approach our ships, and we could easily sail to Sakai on July 17.

 

“On November 6, more than 600 ships and boats from western provinces advanced to Kizu areas.  Kuki Yoshitaka (1542-1600) intercepted the enemy ships and boats.  They besieged our ships, sailing southward, and fought a sea battle from 8 in the morning till around noon.  Kuki seemed to be having a hard battle at first, but, having many big guns in the 6 ships, waited for the enemy ships and boats to come closer, and fired the guns to the enemy flagship to strike it down.  They became panicked and couldn’t approach ours any more.  Kuki finally drove hundreds of the enemy ships and boats into Kizu Bay, and all the audience praised Kuki Yoshitaka for his military exploits.”

 

The first quotation describes how the naval battle in July, 1576 was fought.  In the battle, the navies of the Mori and Kono Clans, whose de facto main force was the Murakami Clan, surrounded Oda sea forces, threw in many earthenware explosives, and burnt down Oda’s ships and boats.  The tactics to cut off each enemy ship surrounding with small fast boats and to attack with earthenware explosives used to be common in the Seto Inland Sea battles.  An earthenware explosive was a round fire bomb.  The bomb has black powder and iron pieces or lead balls covered with earthenware, and popularly used from the Warring States Period till Shoku-Ho Era.  Later, even small rockets with 3 plumes fired with guns, cannons, or wooden cylinders came to be employed.  The explosive powder in their tips exploded when they stroke ships.

 

Those navies who were killed in the battle, including the Manabe Clan, were samurais in Izumi Province, and had strongholds along Osaka Bay, including Otsu in Izumi Province.  They were severely beaten by the navies of the Mori and Kono Clans, whose de facto main force was the Murakami Clan, who was a champion on the Seto Inland Sea at the time, and could not stop the enemy’s shipping military provisions into Osaka Hongan-ji Temple.

 

After the first battle, Nobunaga ordered the Kuki Clan, pirates in Shima Province, to build armored ships and to sail them to Osaka Bay via the Sea of Kumano-nada.  The latter quotation tells us that, in June, the armored ships encountered the besieging enemy navies from Saiga and Tan’nowa shooting arrows and guns, but defeated them with big guns.  The big guns showed their power in November as well to defeat the navies of the Mori and Kono Clans.

 

Just 2 years witnessed a big change in navy battles; from throwing in earthenware explosives to shooting big guns.  The armored ships were not only armored with iron plates to shield the enemy attacks of shooting arrows and guns.  The Correspondences of the Society of Jesus in Japan also reported that the ships were equipped with 3 cannons.  We may well call them battleships with heavy guns.

 

Kano Mitsunobu (1565-1608), a painter of the Kano school, one of the most famous schools of Japanese painting, painted Nagoya Castle in Hizen on a byobu with 6 panels in detail years later.  The castle was a base to sally forth to the Korean Peninsula.  The byobu represented armored ships as well with two-storied or three-storied donjons on top of them.

 

Those donjons might have been spaces for a commander, and symbols of authority and power. The ships had sails, but were usually driven with oars.  Small-sized armored ships were said to have 50 oars, while big-sizes to have more than 150 oars.  They were equivalent to ships with 75-300 of net tonnage, and were equipped with heavy guns, and were crenelated.

 

The structure of the armored ships suggests that they could not sail so fast.  They went to battles with small fast boats guarding them.  In terms of modern navy battles, an armored ship fought as a battleship, a medium-sized boat as a cruiser, and a small boat as a destroyer.  Navy battles were definitely changing, and surpassing in firepower was playing more decisive roles than maneuverability.

 

On land, Shoku-Ho castles with high stone walls, a donjon and towers were getting in all their glory.  Big ships with a high-rise building on top of them and with a lot of guns to shoot from there at enemy ships and boats are opening a new era on the sea as well.

 

Pirates had accumulated their own tactics as sea fighters, but lacked capital reserves to prepare themselves to face the new era with big ships and firepower.  This is the background why the champion in the Seto Inland Sea changed dramatically from pirates such as the Murakami Clan to warlords under the Toyotomi Clan with the capital strength abundant.