Matsukura Shigemasa served as a bushō and daimyō from the Sengoku to early Edo periods.  Shigemasa was the lord of the Yamato-Gojō domain and the first lord of the Hizen-Hinoe (Shimabara) domain.

Shigemasa was born as the eldest son of Matsukura Shigenobu, a retainer of Tsutsui Junkei.  After entering Hinoe as lord of the domain, he governed in a tyrannical and exploitive manner.  The actions committed by Shigemasa along with his son, Matsukura Katsuie, were the primary cause of the Shimabara Rebellion, the largest uprising in Japanese history, against the oppression of Christians by the Edo bakufu.

Period in Iga and Yamato

Similar to his father, Shigemasa initially served Junkei.  In the eighth month of 1584, Junkei died.  The next year, his adopted son and successor, Tsutsui Sadatsugu, was transferred to Ueno Castle in Iga Province and Shigemasa’s father, Shigenobu, followed.  Shigemasa was granted a fief of 8,000 koku in Nabari in Iga and served Sadatsugu.

Later, Shigemasa resided in Yamato Province and became a direct retainer of the Toyotomi family.  In 1600, at the Battle of Sekigahara, Shigemasa served on his own accord for which he was recognized by Tokugawa Ieyasu and became the lord of Gojō-Futami Castle in Yamato.  In Gojō, Shigemasa permitted exemptions from various levies in an effort to stimulate commerce and he developed the town below the castle.

Period in Hizen

In 1615, during the Winter Campaign of the Siege of Ōsaka, based on the support he provided to Yamato-Kōriyama Castle and contributions in battle against Gotō Mototsugu in the Battle of Dōmyōji, in 1616, Shigemasa was granted the former fief of Arima Harunobu totaling 43,000 koku in Hinoe in Hizen Province in Kyūshū.

In 1618, acting in accordance with the policy allowing only one castle per province, Shigemasa abandoned Hara and Hinoe castles and began the construction of Shimabara Castle.  Although his stipend was 43,000 koku, he built a castle on an inappropriately large scale comparable to a daimyō with a fief of 100,000 koku.  As a result, he engaged in severe exploitation of the local population.  In this regard, he conducted a land survey and estimated the yield of his territory to be almost twice the actual amount, and on this basis, he imposed excessive taxes on the local resident.  Based on an appeal from Wada Shirōzaemon Yoshinaga from the village of Chijiwa who performed a role in the construction of Shimabara Castle, Shigemasa had levees built along the coastline of Chijiwa and pine trees planted to block the damage caused by sea salt from the ocean winds.  These pine trees exist to the present day, serving as a wind barrier to protect the town of Chijiwa.

To demonstrate his loyalty to the bakufu, he undertook an official role for the renovation of Edo Castle on a level that was incommensurate with his income and imposed severe measures to manage the expenditures.

Having benefited from trade with the Portuguese, when Shigemasa first assumed his position, he tacitly consented to Christians.  Then, beginning in 1621, he adhered to the policies of the bakufu to suppress Christians.  Initially, these measures were mild, but, in 1625, after Tokugawa Iemitsu (the third shōgun of the Edo bakufu) pointed out that his measures were too generous, Shigemasa was spurred on to enforce more stringent policies.  This included various means of torture such as branding the characters meaning Christian on to the faces of victims or cutting off fingers.  Based on the accounts of the director of the Dutch Trading Company and the captain of Portuguese ships, in 1627, Shigemasa mercilessly tortured and executed Christians as well as peasants who failed to remit their annual rice taxes in boiling water at the Unzen-jigoku, or Unzen Hell, located in a volcanic area in the central portion of the Shimabara Peninsula in Hizen.  In 1629, he recommended to Takenaka Shigeyoshi, the magistrate for Nagasaki, to bring Christians located in Nagasaki to Unzen.

Plans for an expedition to the Philippines

In an effort to appeal to the bakufu with respect to his actions to suppress Christians, he proposed an attack on Luzon Island in the Philippines which served as the base for Christians in the Asian region.  Specifically, he proposed to the rōjū, the highest organ in the bakufu, as follows:

“Luzon is under the control of Spain, and, together with Portugal, they are always eyeing an opportunity to invade Japan.  Therefore, there is a risk that our country will be thrown into chaos.  All of the people who come from Spain to Japan first land in Luzon.  So, I will go with my own army to conquer that country and install my representative there.  If we destroy the base for the Western people, our country will be safe for many years thereafter.  If you allow me to proceed, I plan to sail to Luzon to conquer them.  In return, I request a license to landholdings of 100,000 koku.”

In addition to Shigemasa’s ambition to expand his own territory, he emphasized the risk of an invasion of Japan by Spain in an attempt to justify an attack on the Philippines.  Nevertheless, in the era of Philip II, the King of Spain, the rapid expansion of the Spanish kingdom resulted in chronic shortages of soldiers and, owing to massive debts, a reluctance to acquire additional territories.  As a result, Spain was quickly shifting toward policies to defend their empire.

Tokugawa Iemitsu refrained from promising to dispatch the Japanese army to Manila but nonetheless allowed Shigemasa to investigate the possibility and prepare armaments.  On 12/14 of Kanei 7 (1630), Shigemasa, with the cooperation of Takenaka Shigeyoshi, the magistrate of Nagasaki, sent two retainers (Yoshioka Kurōemon and Kimura Gon-no-jō) to Manila to have them investigate the Spanish defenses.  The retainers disguised themselves as traders and sailed to Luzon under the pretext of engaging in discussions to promote trade.  Each of the retainers was accompanied by ten ashigaru, or foot soldiers, but during a storm on the return voyage, all of those under Gon-no-jō died.  This advance party sent to Manila returned to Japan in the seventh month of 1631, and by the seventh month of 1632, the Spaniards had adopted a highly guarded posture toward the Japanese.

Beginning with Iemitsu, senior figures in the Edo bakufu were interested in pursuing action so engaged in preparations for an expedition including by dispatching the advance party so Shigemasa further increased the taxes on the citizens in his territory to pay for military expenditures.  As part of these preparations, Shigemasa amassed 3,000 arrows and arquebuses. 

Demise and outcome of expeditionary plans

Just before initiating a deployment, in 1630, Shigemasa suddenly died at the Obama hot springs.  He was fifty-seven years old.  There are theories that he was assassinated but the reasons for his demise are uncertain.  Owing to his death, given that he was the commanding officer of the operation, the plans to invade the Philippines stalled.

An investigation of the possibility of an invasion of the Philippines continued in 1637 during the era of Shigemasa’s son, Matsukura Katsuie.  Thereafter, over a period of five years, consideration was given to an invasion of the Philippines but, while oppressed Christian refugees from Japan continued to arrive unabated in Manila, missionaries continued to enter Japan.  Similar to his father, Katsuie acted as a tyrannical lord and viewed Christians as enemies.  While serving as the daimyō of Shimabara, Katsuie was confronted with the last plan for an invasion of the Philippines.

As representatives of the shōgun, daimyō including Katsuie had to supply the forces for an expeditionary army.  This army was envisioned to be comprised of 10,000 men – twice the number initially planned by Shigemasa.  Katsuie was capable of serving as the commander of an invasion of the Philippines, but the Shimabara Rebellion that erupted in 1638 dealt a fatal blow to the plans for this expedition.