Cecilia Holland, widely admired for her historical fiction, published her only SF novel, Floating Worlds, in 1976. It ought to be better known! It is one of my favorites. It’s a space pirates novel. It’s the Mongol Horde in space. It’s a novel of political intrigue. It’s a novel with some of the most compelling characters ever written, especially the tough female main character. (There is one unfortunate turn of phrase in it that may give the contemporary reader pause, but read past that and give the novel the benefit of the doubt.)