Answer :
The supporting details in the given text are:
- In 1167, the Norman forces of King Henry II of England forced their way into England (encouraged by a former exiled Irish king, Diarmat Ma Murchada).
- Over the next hundred years, Norman power waned as the English kings regained control.
What are Supporting Details?
This refers to the evidence which is used to validate a claim or to show that a sentence is true and statistics, facts, and figures are common supporting details.
Hence, we can note that from the given text, the author is talking about Ireland's politics and how they changed in the 12th Century and he gave supporting details to validate the claim that it was now a petty kingdom by talking about the invasion of England.
Read more about supporting details here:
https://brainly.com/question/884525