The 16th-Century manuscripts had been lost for eight decades before being rediscovered at an auction.
We know the excruciating details of Luis de Carvajal's persecution because he managed to keep secret diaries.
But these were not any old notebooks. They were painstakingly crafted, miniature manuscripts with almost microscopic handwriting in Latin and Spanish.
Some pages were intricately decorated with gold leaf he scraped from pages of a Bible.
Each of the three memoirs was no larger than a present-day iPhone, most likely so he could keep them hidden away under his hat.