Date Masamune (伊達 政宗 1567-1636) was one of leading Daimyo in the Tohoku region of Japan.

At age 18, he succeeded his father, Date Terumune, when he retired from the position of daimyo. Shortly afterwards a Date retainer named Ouchi Sadatsuna defected to the Ashina of the Aizu region. On that, Masamune declared war on the Ashina for this betrayal.

When he marched on the Ashina, his army was halted at Hibara by the general Iwashiro Morikuni and was forced to retreat.

The Man Masamune

Masamune is known for a few things that made him a special daimyo of the time. In particular his famous helmet gained him some clout in this period. As a child Masamune Date lost his eye in a bout with smallpox. He actually pulled his own eye out. Masamune expanded trade in the otherwise bland, backwater province of Tohoku. Although initially in his career he was faced with hostile clans attacking him, he managed to overcome these clans after a few defeats and eventually ruled the largest fief of the later Tokugawa shogunate. He built many palaces and worked on many projects to beautify the region. He is also known to have encouraged foreigners to come to his land. It is also possible that Masamune Date himself was secretly a Christian convert although most likely he wanted foreign technology similarly to other lords like Nobunaga Oda. For 270 years Tohoku was a place of tourism, trade and prosperity. Matsushima for instance, a series of islands was praised for its beauty and serenity from the Haiku poet Basho.

Masamune Date's greatest achievment was funding and endorsing one of Japan's only journeys of exploration in this period. Masamune sympathized with Christian missionaries and traders in Japan. In addition to allowing them to come and preach in his province, he also released the prisoner and missionary Padre Sotelo from the hands of Ieyasu Tokugawa. Masamune Date allowed Sotelo as well as other missionaries to practice their religion and win converts in Tohoku. After a while Masamune Date ordered the building of the Date Mura an explorer ship. Masamune constructed this ship using foreign (European) ship-building techniques. He sent one of his retainers and Sotelo on a voyage to Rome. This voyage visited such places as the Philippines, Mexico, Spain and Rome making it the first Japanese voyage to sail around the world. In prior times Japanese lords never funded these sorts of ventures so it was probably also the first successful voyage period.

Although Masamune was a patron of the arts and sympathized with the foreign cause he also was an aggressive and ambitious daimyo. When he first took over the Date clan he suffered a few major defeats from powerful and influential clans such as the Ashina. These defeats were arguably caused by recklessness on Masamune's part. No lord fully trusted Masamune Date. Hideyoshi Toyotomi reduced the size of his land after his tardiness to participate in the siege of Odawara against Ujimasa Hojo . Later in his life Ieyasu Tokugawa increased the size of his lands again but constantly was suspicious of Masamune and his policies. For instance Ieyasu Tokugawa suspected foreign missionaries as treasonous and/or a threat to his power. Because of this he ordered Padre Sotelo to death after his journey around the world. Although Ieyasu Tokugawa and other allies of the Date were always suspicious of him, Masamune Date served the Tokugawa and Toyotomi loyally for the most part. He took part in the Korean campaigns, Hideyoshi's campaigns for expansion in Korea and the Osaka campaigns. When Tokugawa was on his deathbed Masamune came to visit him and read a piece of Zen poetry to him.