right|thumb|Nitta Yoshisada
also known as Minamoto no Yoshisada was a samurai lord of the Nanboku-chō period Japan. He was the head of the Nitta clan in the early fourteenth century, and supported the Southern Court of Emperor Go-Daigo in the Nanboku-chō period. He famously marched on Kamakura, besieging and capturing it from the Hōjō clan in 1333.
Later, he fought the Ashikaga brothers on the Emperor's behalf in a see-saw campaign which saw the capital change hands several times. After a peaceful compromise was agreed, Yoshisada was entrusted with two royal princes. At the siege of Kanegasaki (1337), both princes were killed, along with Yoshisada's son, although Yoshisada was able to escape. He committed seppuku when his horse was killed at the siege of Kuromaru.
Early life
Yoshisada was born in 1301, the eldest son of Nitta Tomouji. He succeeded his father and became the lord of Nitta Manor in Kōzuke Province in 1317. At this time, he also became the head of the Nitta clan. Yoshisada courted a daughter of a court noble, Kōtō-Naishi (匂当内侍), and married her through the emperor's mediation.
Taiheiki states,
He therefore speaks to Ryūjin who, he has heard, is a manifestation of Amaterasu.
The stele at , the tiny bay west of Inamuragaki, says: <blockquote>666 years ago on May 21, 1333 Nitta Yoshisada, judging an invasion on land to be difficult, decided to try to bypass this cape. This is the place where, according to tradition, he threw his golden sword into the waves, praying the sea-god He took the Seiwa Genji heirloom Higekiri and the Tenka-Goken Onimaru Kunitsuna.
Later campaigns
thumb|Nitta Yoshisada fighting bravely with the two swords Onikiri and Onimaru at the Battle of Minatogawa (1336)
During the following few years, Nitta Yoshisada's rivalry with Ashikaga Takauji and his brother Ashikaga Tadayoshi came to a head, with an imperial commission to destroy the two brothers issued in 1335. The two armies fought a number of battles, starting at the Yahagi River on December and ending at Mishima later that month. Yoshisada's forces were eventually defeated and the brothers advanced upon Kyoto.
Nitta retreated with the emperor to Hieizan. Eventually, on November 13, 1336, the emperor agreed with Takauji's offers to return to Kyoto. Before he did so, he entrusted Nitta with escorting Prince Takanaga and Prince Tsunenaga to Echizen Province. They made it as far as a loyalist stronghold, where they had to endure the siege of Kanegasaki (1337). Nitta escaped, but his son Nitta Yoshiaki and the princes were eventually killed. Yoshisada died on August 17, 1338.