What did the Treaty of Japan do to the country?

Question

sources would be great

Answer 1

I don't know which treaty you are referring to. But, if you mean the Peace Treaty which officially ended World War Two and was signed in 1951, the occupation of Japan ended about four years later. It would have ended sooner, but the UN Peace Enforcement Mission in Korea required we maintain bases close to the Korean Peninsula.
Enter the term "Post-War Japan" into a search engine and you will be absolutely flooded with sources.