How was the idea of self-determination affected by the peace treaties ?

"It was violated almost immediately" is the right answer.

Self-determination was a secret talking of president Wilson and the ideas behind the League of Nations. The principle of self- determination, often regarded as a moral or constitutional right is that each country is authorized to have a sovereign territorial state in which every identifiable community would decide the state with which they belong.

It was violated because not all the citizens got a country, and when the boundaries of nations were being rearranged many groups of people were forced to remain in different countries. Hence, it was violated almost immediately.

Poaching is the right word I would think.

Explanation: Sorry if wrong.