In his new book Bannon: Always the Rebel, author Keith Koffler highlights the six books other than the Bible that former White House chief strategist Stephen K. Bannon says most influenced his worldview.

Koffler points out that “[c]entral to Bannon’s thinking about America is his thinking about Western civilization, its Judeo-Christian tradition, and his own Catholic faith.” That said, it should come as little surprise that three of the books Bannon listed to Koffler have to do with Christianity.

1. The Imitation of Christ. Bannon believes this work, attributed to Thomas à Kempis, was actually written by Groote and transcribed by Groote. This book is regarded as the second-most important book next to The Bible because it counsels the world in humility and exemplifies how faith in Jesus Christ will help people in their ultimate struggle to attain inner peace. Bannon believes strongly in the importance of knowing ones self. His very personal decision to stop drinking, following a revelation, exemplifies this practice of self-awareness.

2. The History of the Decline and Fall of the Roman Empire by Edward Gibbon. This 18th century masterpiece is one of the most important literary works to Bannon due to its powerful language and his belief that it provides a critical look at the “people most like us,” the Romans. Bannon believes the book plays an important role in highlighting the same dilemma facing the United States today where the political system has been “bought and paid for by the elites” and ultimately weakened due to lack of national identity; the very same thing the Romans faced and which led to a changing of its culture and ultimate destruction of civil society.

3. The Brotherhood of the Common Life and Its Influence by Ross Fuller. This book described the formation of a medieval religious movement that was born in the Catholic Church and which gave way to Protestantism. Koffler writes, “Gerard Groote (1340–1384), described by Ross as the founder and early “focal point” of the Brotherhood (or Brethren) of the Common Life, is a key figure for Bannon. Groote was, like Bannon, a voracious reader, but Groote came to believe it was more important to have the right knowledge than all knowledge.”

4. Thucydides’ History of the Peloponnesian War. This book provided Bannon with lessons against an interventionist foreign policy, and he says it teaches about the law of unintended consequences. “That’s what Thucydides teaches. It’s just very powerful. All leaders should read it. You just see the frustrations. You see the mistakes made, you see good men trying to do the right thing for their cause. All the failures, and the successes. But principally the failures.” He sees this same lesson being relived through Western Civilization’s battle against radical Islam and the mistakes made over the past few years have strengthened his belief that the Washington elite, liberals and the neocons havestill have not learned the lessons of Thucydides or Halberstam, Koffler notes.

5. The Spiritual Exercises of St. Ignatius of Loyola. This book teaches the importance of performing a daily “examen” or devotional exercise that involves a reflection and moral evaluation of where one’s life is and where it’s going. Bannon performs a personalized “examen” daily and has since made the decision to eradicate alcohol from his life. “I’m not saying I’ve accomplished a lot in my life, but what I have accomplished is because of that set of practical tools that I was able to find,” Bannon said. “People go, ‘How did all this stuff come together?’ Because I gave it conscious thought. I had the ability to really step back and really think it through.”

6. Plutarch’s Lives of the Noble Greeks and Romans. Bannon says this book teaches about the virtues that politicians must have to lead wisely and avoid military catastrophes. “Anybody who wants to get in politics or to know about power and know about, not just military action, but how men react in situations, has to read Plutarch’s Lives” Bannon says in Koffler’s book. “What Plutarch does is take a Greek and a Roman. He writes a biography of one and then writes the biography of the other, and then he compares and contrasts. He has an analysis. That’s the power of it. The analysis is how Greek society was, how Roman society was, and then the analysis of the character of both” biographical subjects, Bannon says. He sees America as the new Rome and believes it is foolish for the west to turn a blind eye away from history’s plentiful lessons.

In addition to these six books which helped shape his worldview, Bannon also references Guénon’s Man and His Becoming According to the Vedanta as a powerful read in that it highlights the importance of being able to come off the so-called “wheel of life” and reflect on ways that the individual can improve and become better through self-awareness.

After Trump won the historic 2016 election, Bannon said he gave colleagues copies of David Halberstam’s The Best and the Brightest to warn them against excessive pride or hubris. He described that the book highlighted the way the elite of the Democratic Party in Washington, D.C. dragged America into the Vietnam War “didn’t have a lot of character, they didn’t really understand the lessons of what Indochina was saying, what the people were saying. And they didn’t have the quality of character to drop the arrogance, this Western arrogance, this elitism, that, ‘I know After Trump won, everything, I’m the smartest guy.'”

Bannon: Always the Rebel is available for purchase at bookstores and online.

Adelle Nazarian is a politics and national security reporter for Breitbart News. Follow her on Facebook and Twitter.