In fact, it's hard to find any in-depth Basque history. Am I searching in the wrong places or has this topic really gotten so little attention?
Any books written by mark kurlansky have segments of the history you’re searching for, the most extensive basque history library is located on the University of Nevada Reno campus, they would be glad to send you any articles you’re seeking.
Roger Collins, The Basques (Oxford: Blackwell, 1986) is what you want to consult.
The topic has gotten enough attention, but naturally you would need a reading knowledge of Spanish to really go in-depth with Basque historiography.