was a Japanese samurai

Samurai

is the term for the military nobility of pre-industrial Japan. According to translator William Scott Wilson: "In Chinese, the character 侍 was originally a verb meaning to wait upon or accompany a person in the upper ranks of society, and this is also true of the original term in Japanese, saburau...

 of the Sengoku period

Sengoku period

The or Warring States period in Japanese history was a time of social upheaval, political intrigue, and nearly constant military conflict that lasted roughly from the middle of the 15th century to the beginning of the 17th century. The name "Sengoku" was adopted by Japanese historians in reference...

 through late Azuchi-Momoyama period

Azuchi-Momoyama period

The came at the end of the Warring States Period in Japan, when the political unification that preceded the establishment of the Tokugawa shogunate took place. It spans the years from approximately 1573 to 1603, during which time Oda Nobunaga and his successor, Toyotomi Hideyoshi, imposed order...

, who served the Tokugawa clan

Tokugawa clan

The was a powerful daimyo family of Japan. They nominally descended from Emperor Seiwa and were a branch of the Minamoto clan by the Nitta clan. However, the early history of this clan remains a mystery.-History:...

, and became a daimyo in 1590. Ietada was the eldest son of Matsudaira Koretada, the head of the Fukōzu

Matsudaira clan

The was a Japanese samurai clan that claimed descent from the Minamoto clan. It first originated in and took its name from Matsudaira village, in Mikawa Province . Over the course of its history, the clan produced many branches, most of which also centered around Mikawa Province...

 branch of the Matsudaira clan. Ietada served Tokugawa Ieyasu

Tokugawa Ieyasu

 was the founder and first shogun of the Tokugawa shogunate of Japan , which ruled from the Battle of Sekigahara  in 1600 until the Meiji Restoration in 1868. Ieyasu seized power in 1600, received appointment as shogun in 1603, abdicated from office in 1605, but...

 from a young age, and fought in many of Ieyasu's campaigns. Upon the latter's entry into the Kantō region

Kanto region

The is a geographical area of Honshu, the largest island of Japan. The region includes the Greater Tokyo Area and encompasses seven prefectures: Gunma, Tochigi, Ibaraki, Saitama, Tokyo, Chiba, and Kanagawa. Within its boundaries, slightly more than 40 percent of the land area is the Kantō Plain....

 in 1590, Ietada was granted the 10,000 koku

Koku

The is a Japanese unit of volume, equal to ten cubic shaku. In this definition, 3.5937 koku equal one cubic metre, i.e. 1 koku is approximately 278.3 litres. The koku was originally defined as a quantity of rice, historically defined as enough rice to feed one person for one year...

 fief of Oshi

Oshi Domain

The ' was a Japanese domain of the Edo period, located in Musashi Province. It was headquartered in Oshi Castle.-List of Daimyo:* Matsudaira clan # Ietada* Matsudaira clan # Tadayoshi...

. Oshi had been meant for Ieyasu's fourth son Tadayoshi; however, as Tadayoshi was still young, the fief was entrusted to Ietada's stewardship. When Tadayoshi came of age, he was granted Oshi, and Ietada was moved to the Omigawa Domain

Omigawa Domain

was a minor Japanese domain of the Edo period, located in Shimōsa Province , Japan. It was centered on what is now part of the city of Katori. It was ruled for most of its history by the Uchida clan....

 in Shimōsa Province. Ietada was assigned to Fushimi Castle

Fushimi Castle

', also known as Momoyama Castle or Fushimi-Momoyama Castle, is a castle in Kyoto's Fushimi Ward. The current structure is a 1964 replica of the original built by Toyotomi Hideyoshi.-History:...

 together with Torii Mototada

Torii Mototada

was a Japanese samurai of the Sengoku period through late Azuchi-Momoyama Period, who served Tokugawa Ieyasu. Torii died at the siege of Fushimi where his garrison was greatly outnumbered and destroyed by the army of Ishida Mitsunari...

; the two men died in battle there, shortly before the Battle of Sekigahara

Battle of Sekigahara

The , popularly known as the , was a decisive battle on October 21, 1600 which cleared the path to the Shogunate for Tokugawa Ieyasu...

.

Ietada is famous for his journal, , which he kept for the 17 year interval between 1575 and August of 1594.