Azai Nagamasa

Azai Nagamasa (浅井 長政^?, 1545 – August 28, 1573) was a daimyō during the Sengoku period of Japan. His clan, the Azai, were located in northern Ōmi Province, east of Lake Biwa. He was both the brother-in-law of Oda Nobunaga, starting in 1564, and one of Nobunaga's enemies from 1570 to 1573. Nagamasa and his clan were destroyed by Oda Nobunaga in August 1573. Major battles of Azai Nagamasa include the battle of Anegawa in 1570 and the many sieges of Odani castle between 1570 and 1573.

Azai Nagamasa was the son of Azai Hisamasa, from whom he inherited clan leadership in 1560. Hisamasa had been compelled to step down by many of his retainers in favor of his son, Nagamasa. Hisamasa retired, and would later commit suicide along with his son in August 1573. Nagamasa successfully battled both Rokkaku Yoshikata and Saitō Tatsuoki between 1560 and 1564. He is remembered as being a capable commander of troops on the battlefield.

He married Oda Nobunaga's sister Oichi in 1564. Nobunaga desired peaceful relations with the Azai clan because of their strategic position in between Oda clan land's and the capital, Kyoto.

In 1570, Oda Nobunaga declared war on the Asakura family of Echizen. The Asakura and Azai had been allies since the time of Nagamasa's grandfather. This sudden war between two Azai clan allies is reported to have divided the clan. Many retainers wished to honor the alliance with the Asakura, while Nagamasa himself is reported to have favoured staying neutral, essentially siding with Nobunaga. In the end, the Azai clan chose to honor the generations-old alliance with the Asakura and came to their aid. Initially, this decision caused Nobunaga's army, which was marching upon the Asakura's lands to retreat back to Kyoto. However, within a few months the forces of Nobunaga were again on the march, but this time they marched on Azai lands.

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