Review Detail of Adearic in The Martial Unity

aroud chapter 600 i fond a mistake in the World build,thé tribe on thé Island dont have technologies so it's assume thé tribe can't have Martial Squire and above, but has the chapter continue the chef of the tribe is a Martial senior and the tribe have multiple martial Squire it's no that Bad but it strange to read AT first.other than this mistake it's a great storyand if someone Can explane the mistake above to me? i could have mis an explanation.