Big Five book publishers are made up of imprints, for Milo
Publishing 101: The Big Five houses are made up of imprints
To understand publishing's right-wing imprints, first you have to understand how modern American book publishing is organized.
American trade book publishing is dominated by five publishing houses, known as the Big Five: Penguin Random House, HarperCollins, Hachette, Macmillan, and Simon & Schuster. Of these, Penguin Random House is the biggest, Macmillan is the smallest, and Simon & Schuster sits comfortably in the middle.
Together, these five publishing houses make up over 80 percent of the US trade publishing market share -- meaning that they produce over 80 percent of the kinds of general-interest books that get sold in Barnes & Noble. The remainder is published by smaller independent presses, and those independent presses usually have specific areas of specialty. But the Big Five houses don't need to specialize, because they can do that on an imprint level instead of a company level.
Milo Yiannopoulos represents something new in conservative trade publishing.
Milo Yiannopoulos is not a run-of-the-mill conservative thinker. His brand is ostensibly a winking, provocative, speaking-truth-to-power punk rock ethos -- hence the title of his forthcoming book, Dangerous. But that image only rings true if you think that women, people of color, trans people, and other historically disenfranchised people have too much power over white cis men and need to be put in their place.
That is what Yiannopoulos believes deeply. And while many more mainstream conservative thinkers would agree with him that liberals have a stranglehold on the culture and bully those who disagree with them, Yiannopoulos's tactics are extreme even by their standards.