Once More with Endnotes

Since language has a tendency to change over time and certain references lose their currency, reprints of classic works of literature sometimes have an endnotes or footnotes section, explaining some of the references. These usually explain:
 * Customs, technological devices and societal statuses of the time period that are no longer recognized.
 * Word uses which have since shifted, and wordplay about such.
 * Connections with the author's life period, and random guesswork at what inspired passages
 * Allusions or in-references that were commonly recognized, but are now more obscure.

Often parodied by having footnotes for footnotes.

Not to be confused with Once More .


 * The Bible. There are whole books dedicated to endnoting the thing.
 * The Pickwick Papers
 * Crime and Punishment
 * Frankenstein
 * The Brothers Karamazov
 * War and Peace
 * Anne of Green Gables. One amusing bit is the annotating author observing that somehow Anne obtained a copy of Ben-Hur two years before it was published.
 * Annotated editions of anything by Shakespeare, obviously.
 * Many compilations of stories by H.P. Lovecraft.
 * Alice in Wonderland - as a lot of the poems and songs were parodies of ones no longer known.
 * Beowulf
 * Gulliver's Travels - dozens of political and literary references entirely opaque to the modern reader.
 * War of the Worlds
 * Don Quixote: Sancho uses many proverbs and Spanish idioms that get lost in translation. There are also many allusions to chivalrous knights, courtly love and mythology that most people are not even aware of today.
 * Anything by Thomas Hardy - the man peppered his novels with classical allusions.
 * The Divine Comedy. As it's a number of Take Thats against then-current political enemies, it's sometimes impossible to figure out why someone is in a certain level of the afterlife without endnotes. Dante will sometimes explain it, but other times, he'll just assume that the reader knows the subtext. Many of the gestures, insults, and metaphors are also unknown to modern audiences.
 * Paradise Lost. It's probably possible without the notes, but boy, does it make life a lot easier.
 * The Rime of the Ancient Mariner. The writer himself had to write Cliff Notes so that his friends could understand it.
 * There are at least a few different Annotated Sherlock Holmes collections in the world. The one This Troper has is almost surreal, as all annotations follow the Literary Agent Hypothesis, and therefore explain not only Victorian references, but also point out mistakes Watson clearly made in writing the story, and explanations of continuity errors.
 * Isaac Asimov's Annotated Gilbert and Sullivan.
 * T. S. Elliot provided some endnotes of his own for his poem "The Waste Land"; the poem includes untranslated quotes from various sources. Unfortunately, the endnotes are sometimes almost as obscure as the poem itself.
 * Romance of the Three Kingdoms. This troper's translation is loaded with endnotes explaining all sorts of aspects of ancient Chinese culture, from date conversions to the characters' frequent references to earlier historical characters, as well as notable places where the most commonly read version of the text was significantly changed from the original. There are over 100 pages of endnotes, but it is an over 2000 page long novel.
 * Sometimes, non-Western literature, especially translated versions of Japanese literature/light novels such as Welcome to The NHK have endnotes to explain even contemporary references which may seem obvious to a Japanese person if they are rooted in the context of the novel, but a Western person like an American or a different English speaking person might miss.
 * All of Jane Austen's works.
 * Pepys's Diary has so many endnotes they take up an entire volume, with another volume of general reference.
 * James Joyce's Ulysses has received this treatment with at least one annotated edition explaining the book's numerous references and allusions.
 * Notable for the fact that the book of annotations is bigger than Ulysses itself.
 * Lolita--not because it was written particularly long ago, but because it's packed with allusions and sneaky wordplay.
 * The Flashman series has this as well. Like the Sherlock Holmes example above, the endnotes play with the Literary Agent Hypothesis, and as well as explaining the various allusions and Victorian pop-culture references, point out occasions on which the eponymous character must have been mistaken, or exaggerated for effect.
 * Sun Tzu's The Art of War is understandable (although much of it is obsolete), but most printings will have at least an essay providing historical context, if not extensive notes.
 * In an unusual case, almost all editions of The Art of War have annotations from multiple classical-era authors, most notably Cao Cao. These make up 80% or so of the book and are normally considered an indispensible part of the text, providing far more information than the original work. Modern-era authors will then add a second set of notes.
 * Not quite endnotes, but there is at least one reference book listing the allusions in The Cantos of Ezra Pound that is longer than the actual cantos.