The issues in the collection first appeared in 1993, 1994 and 1995. The collection first appeared in paperback and hardback in 1996.
Warning: Wikipedia contains spoilers
It belongs with the second collection, The Doll's House, and the fifth, A Game of You, in that it finishes off a story that mostly originated in these collections. Parts from other collections are also important to its story, however, notably elements from Season of Mists and the story of Orpheus, told mostly in Fables and Reflections.
The most structurally ambitious of the collections, The Kindly Ones is a single storyline written as a Greek tragedy, with Morpheus as its doomed hero and an aspect of the triad of witches, the Hecatae, as the Greek chorus. It pulls together various threads left dangling throughout the series, notably the grudges against Morpheus of several characters; Hippolyta Hall, the mother of one of Morpheus' children (the child Daniel), the witches themselves, the Norse god Loki, and the witch Thessaly. After Daniel disappears, Hippolyta convinces herself that Morpheus must be responsible, although this is not in fact the case; the child is apparently stolen by Loki and Robin Goodfellow (the Puck). Hippolyta sets out to destroy Morpheus, and is eventually led to the witches themselves, in their aspect as the Furies. They are empowered to destroy Morpheus by the fact that he has shed the blood of one of his family (that of his son, Orpheus, when he granted him the boon of death).
The Kindly Ones also continues several other stories, including that of Cluracan of Faerie and his sister Nuala, and that of Rose Walker and her former landlord Hal. It also features Lucifer, playing piano in a nightclub; although he is loath to take requests.
Throughout the story the greatest mystery is the motivation of Morpheus; it is never exactly clear to what extent he is aware of the course on which has, to some extent, set himself, and how serious are his attempts to save himself. In a telling sequence, he finally lays himself open to the Furies by leaving his kingdom to fulfil a boon he had granted to Nuala, even though he knows that his own end is most likely the consequence of this action; once more his refusal to shirk what he perceives as his responsibilities for any reason is a vital point in the story. In an affecting sequence, the main story ends with Morpheus and his sister Death on a desolate peak, echoing a sequence from one of the series' early high points, "The Sound of her Wings" (issue #8). Death asks for Morpheus' hand, and he simply disappears, in a flash of light.