Rich countries bent on power and profit have also exported to them the "cynicism of a world without God", Pope Benedict writes according to a Reuters report.
The Pope also condemns drug trafficking and sexual tourism, saying they are signs of a world brimming with "people who are empty" yet living among abundant material goods.
One section of the book was printed in Wednesday's Corriere Della Sera daily before publication later this month by Italian publisher Rizzoli, which owns the newspaper.
A Rizzoli spokeswoman confirmed the authenticity of the excerpts.
In the 400-page book, called Jesus of Nazareth, the Pope offers a modern application of Jesus's parable of the Good Samaritan, who stopped to help a man who had been robbed by thieves when others, including a priest, had not.
"The current relevance of the parable is obvious," the Pope writes.
"If we apply it to the dimensions of globalised society today, we see how the populations of Africa have been plundered and sacked and this concerns us intimately," the pope says.
He drew a link between the lifestyle of people in the developed world and the dire conditions of people in Africa.
"We see how our lifestyle, the history that involved us, has stripped them naked and continues to strip them naked," he writes.
Pope Benedict, who has condemned the effects of colonialism before, said rich countries had also hurt poor countries spiritually by belittling or trying to wipe out their own cultural and spiritual traditions.
The Pope says his comments were valid for other regions apart from Africa.
Citing other passages from the book, the EarthTimes says that the pope also draws from Karl Marx's theory of alienation.
"Karl Marx describes man's alienation in a drastic way; although by limiting his reasoning to the material sphere he fails to reach the true depths of alienation, he nevertheless provides a clear image of the man who falls victim to the robbers."
"Is it not true that man ... during the full course of his history, finds himself alienated, mangled, abused?" the pope writes.
The book, his first since his election as pope two years ago, is due to be published on 16 April, the day of his 80th birthday, in Italian, German and Polish.
Rich nations plundered third world: Pope (News.com.au, 5/4/07)
Pope Benedict XVI cites Marx in his new book on Jesus (EarthTimes, 4/4/07)
5 Apr 2007