A Bit of Historical Context
Before diving right into Ghost of Tsushima, it’s worth having a bit of historical background regarding when it’s set, the samurai themselves, and the Mongol invasion itself.
Ghost of Tsushima takes place during the first of two Mongol invasions of Japan, though neither were successful. This also marked the first time that Japan had faced a foreign power in battle.
This is important because of the way that Samurai typically fought. Even in an outright war, Samurai would call out by name someone from the enemy ranks, and then attack in 1v1 combat. Even when using a bow and arrow, the Samurai abided by this respectful, 1v1 combat.
In contrast, the Mongols were far more ruthless in combat. They took no notice of the Samurai’s combat customs and rushed forward en masse, grappling with individuals they could catch and killing them. The Mongols also introduced the method of firing multiple arrows at once into Japan at the time, which again was at odds with the way Samurai fought.
While no love was lost between the two sides — it is a war, after all — the Samurai massively disapproved of the way the Mongols took to combat.