You're opening up a big can of worms here, but see this subreddit's FAQ on the subject.

I would recommend big names like

Jonathan Riley Smith

Helen Nicholson

Maurice Keen

that will give a pretty good overview, which would serve you much better in forming your own opinion than anything you'll find readily available through google.

Hopes this helps a little. Happy Reading!

Edit I'd also add John France and Norman Housley to the list.

This submission has been removed because it violates our '20-Year Rule'. To discourage off-topic discussions of current events, questions, answers and all other comments must be confined to events that happened 20 years ago or more.

Although the second part of your question is justifiable (although I would check the FAQ first), the reference to Obama is only going to invite political discussions. If you want to recompose your question to remove reference to current events, you can resubmit it.