ENGLISH: Very good historical review of the five great heresies against the Catholic Church along its history:
1. Arianism, taken as a typical heresy of the first centuries that denied one or two important Catholic beliefs but kept the others.
2. Islam, which started as a simplification of Catholic tenets that started outside the Catholic realm, and ended as a separate religion. One of the most lucid historical treatments of Islam I have read, sometimes almost prophetic.
3. Albigensians (Catharism), a revival of old Gnostic/Manichaean trends, a suicidal heresy, as it forbade sex, considered as a weapon created by the Devil (the evil god), but that threatened to conquer all of Christendom. Although Belloc does not mention it, the current attempt by nationalist Catalonians to defend them is just a show of historical ignorance.
4. Protestantism (especially Calvinism), which rather than a typical heresy is a bunch of different denials of different basic Catholic tenets, its different branches united by a common hate to Catholicism. Although this has changed somewhat since Belloc wrote the book (1936-38), some sediment of this can be observed even now
5. The present attack against Catholicism by the dominant ideology. This chapter could have been written now. Things are now much worse than when the book was written, but all the trends signaled in the book are quite visible now.

ESPAÑOL: Muy buen repaso histórico de las cinco grandes herejías contra la Iglesia Católica a lo largo de su historia:
1. El arrianismo, entendido como una herejía típica de los primeros siglos, que negaba una o dos creencias católicas importantes, pero conservaba las demás.
2. El Islam, que comenzó como una simplificación de los principios católicos, que comenzó fuera del ámbito católico y terminó como una religión separada. Uno de los tratamientos históricos más lúcidos del Islam que he leído, a veces casi profético.
3. Albigenses (catarismo), resurgimiento de las viejas corrientes gnósticas/maniqueas, herejía suicida, ya que prohibía el sexo, considerado como un arma creada por el diablo (el dios del mal), pero que amenazaba con conquistar a toda la cristiandad. Aunque Belloc no lo menciona, el intento actual de los nacionalistas catalanes por defenderlos es solo una muestra de ignorancia histórica.
4. El protestantismo (especialmente el calvinismo), que más que una herejía típica es un montón de negaciones diferentes de distintos principios católicos básicos, sus diferentes ramas unidas por el odio común al catolicismo. Aunque esto ha cambiado un poco desde que Belloc escribió el libro (1936-38), aún ahora se pueden observar algunos sedimentos de ello.
5. El ataque actual contra el catolicismo por parte de la ideología dominante. Este capítulo podría haber sido escrito ahora. Las cosas están mucho peor que cuando se escribió el libro, pero todas las tendencias señaladas en él son bastante visibles hoy día.

A easy and fascinating read of the 5 great heresies of Arianism, Mohammedism, Albigensianism, Protestantism and Modernism.

أُلِف الكتاب قبل مئة سنة من مؤلف كاثوليكي متعصب. البدع الكبيرة يقصد فيها خمس بدع بوجهة نظره ظهرت مضادة للمسيحية الكاثوليكية بنظره، هي الأريوسية والإسلام (يسميه المحمدية والذي يدعي أنه بدعة كاثوليكية ) وبدعة الكاثار والكالفينية واخيراً بدعة الحداثة. تعصب المؤلف وانعدام حياديته جعلت الكتاب لا يستحق القراءة.

Required reading for modern Catholics.

The only way to know where you are going is to know where you came from. This book is more applicable today than ever with predictions that ring eerily true in consideration of its history.

Magnificent. Erudite. Historical. Impassioned while being deeply rational. Belloc was a genius.

And, refreshingly fair. Careful to tell the story from both sides, he draws conclusions that are convicting because of their historical accuracy and theological reasonableness.

I leaned a lot and will certainly re-read. My only regret is that I read this AFTeR John Senior’s “Death Of Christian Culture.”

I've heard good things about Hillaire Belloc, such as that he was one of the great historians of the 1900s. A prolific writer, he seems to have written many a treatise, and, in skimming his books, you can tell he didn't neglect a fruitful reading schedule either. Every sentence seems to be a summary of a wealth of history. Furthermore, he's often called a prophet of his day, making incredibly accurate predictions of the flow of the events throughout humanity.

I was not disappointed in reading this book. He lives up to his high reputation, which is something few men can claim.

In this book, he mainly hones in on Arianism,Islam, Albigensianism, Protestantism(or more generally put, Calvinism. When referring to the former he often means the latter, and explains why in the book), and what he dubbed (and so we now call) Modernism.
He makes a couple predictions of the future of Modernism and Islam (and this is before they became what they are today) and was spot on in nearly every analysis.

His analytic presentation and style was very pleasant to read and kept me intrigued. He unveils events and factors most do not know about the heresies in questions such as: what gave them their survival power and how they might have reappeared or affected each other.

Lastly, he doesn't turn a blind eye to the faults of certain groups within the church that lead up to the Protestant reformation, which I appreciated. When I'm reading a book, there is a lists of things that produce annoyance in me and one of those things is the glorification of 'your side' because it is 'your side' and ignoring whatever faults committed by the people on 'your side.'

5 stars all in all
I don't really have any complaints.

Some parts are almost prophetical in their accuracy especially regarding the state of Islam and the future of the modern heresy.

Très intéressant et documenté. Que l'on soit croyants ou non on assiste ici à une analyse historique et sociale autour de plusieurs grandes hérésies qui ont marqué celle ci.
C'est la première fois que je lis Belloc. Son style est incisif mais fluide et agréable à lire.

It's a must-read

Prescient. If you want to understand what is happening in the world today, this book will be most illuminating. The last chapter is exceptional.

Anything by this author

I wish I could rate this with negative amounts of stars... I did not like it what so ever because I had to read it for school

Excellent, informative and somewhat prophetic.