He first fought as a samurai in the Anglo-Satsuma War. He was part of the Satsuma forces in the Boshin War to overthrow the Tokugawa Shogunate. After the Meiji Restoration he was appointed commander of the Imperial Guards.
He also served as field commander in the suppression of various insurrections during the early years of the Meiji era, including the Hagi Rebellion and the Satsuma Rebellion.
Kawamura led his Imperial Guards Division in the First Sino-Japanese War and went to the front in Taiwan as field commander. On the conclusion of that war, he was ennobled by Emperor Meiji with the title of danshaku (baron) under the kazoku peerage system.
In the Russo-Japanese War of 1904-1905, Kawamura succeeded Prince Fushimi Sadanaru as commander of the Japanese 10th Division, and served notably as field commander at the Battle of Yalu River (1904). In January 1905, being promoted to General, he was appointed Commander of the Japanese Fifth Army and took part in the Battle of Mukden.
After Japan"s victory, Emperor Meiji elevated him to the title of shishaku (viscount).
After the war, Kawamura served as chief of the Tokyo Garrison, and in 1915 he became a field marshal. Kawamura"s grave is at Aoyama Cemetery in Tokyo.