Joseph Campbell had a very interesting life trajectory. In his early ages, he was fascinated by the American Indian fairy tales and later decided to study humanity for his college and graduate education. While in college, he was among the fastest half-mile runners in the world. After a trip to Europe as part of his doctoral fellowship from Columbia University, he withdrew from the PhD program and lived in a shack in the woods for five years doing independent study. The living cost of this hermit period came from his earlier earnings as a Rock band member. At the end of this hermit period, he accepted a professor offer at Sarah Lawrence College and worked there 38 years till his retirement. He married one of his student, had no children, and passed away at the age of 83.
This book is his first book and also arguably the most famous one. It ranks number 30 in the TIME magazine’s all TIME 100 best non-fiction books since 1923.
In this book, Professor Campbell presented his view that all myths, fairy tales and religious stories are essentially the same, which he calls the mono-myth. And that mythologies to the collective unconscious is dreams to the personal unconscious.
Dream is personalized myth, myth is depersonalized dream. — Joseph Campbell
The following video summarizes the mono-myth theory very nicely
There are a series of his lectures on Youtube and you can see that he is a very intense person.