- Birth: 1563
- Death: 1631
- Title: Samanosuke
- Son: Kato Akinari
- Distinction: Oda, Toyotomi, Tokugawa retainer, one of the Seven Spears of Shizugatake
Yoshiaki first distinguished himself at the Battle of Shizugatake (1583), where he would be remembered as one of that struggle's 'Seven Spears'. He went on to become a naval commander for Toyotomi Hideyoshi and commanded ships in the Kyushu and Odawara Campaigns, after which he was given a 100,000-koku fief in Ise province at Matsuzaki. He was involved in the bitter naval battles fought off the coast of southern Korea during the 1st and 2nd Korean Campaign, many of which went in favor of the Korean navy. Following the death of Hideyoshi (1598) Yoshiaki drifted in Tokugawa Ieyasu's camp and fought for him during the Sekigahara Campaign (1600). At the Battle of Sekigahara he commanded 3,000 men in the Tokugawa vanguard and clashed with the forces of Shima Sakon. After the battle his fief was increased to 200,000 koku.
- Initial text from Sengoku Biographical Dictionary (Samurai-Archives.com) FWSeal & CEWest, 2005