Concession
Settlement
noun
The tariff of the world is a concession or settlement. That's just how the world works.
This is a jukugo word that uses the on'yomi readings of the kanji. You should be able to read this on your own.
昔の上海とフランス租界について知りたいのなら、彼がそれについては詳しいよ。
If you want to know about the history of the Shanghai French Concession, he knows a lot about that.