Image: Sucker Punch Productions / PlayStationOfficial screenshot from Sucker Punch Productions / PlayStation.
Lord Kazumasa Sakai is Jin's father and the former head of Clan Sakai. He died in a raider ambush on Iki Island while Jin watched, frozen with fear. That memory haunts Jin through the whole game and drives the Iki Island expansion.
Kazumasa was a skilled commander and a fierce swordsman, known for scouting unfamiliar ground fast and flanking enemies. His soldiers said he once broke an opponent's blade in a duel. A group of rebels in Chikuzen gave up on the spot. After his wife's death he poured his grief into fighting and became a distant father.
On the jito's orders he led the samurai invasion meant to bring Iki's raiders and pirates to heel. He brought the young Jin along. The campaign displaced and killed many innocents. Earlier visits to Iki also put him face to face with the Viper and the pirate Black Hand Riku.
He appears in flashbacks and hallucinations in the Iki Island story. His armour is the Sakai Clan Armor Jin can reclaim from the family home. His horse armour is tied to the Iki Mythic Tale The Legacy of Kazumasa Sakai.
Raiders trapped his force in Senjo Gorge. He cut down dozens of them before going down, likely with a broken leg, and begged Jin for help. The raider Tenzo landed the killing blow.