You can't keep Anonymous down. The most recent heralded appearance of this ubiquitous author was as the title of a film that's already faded, but not without kicking up debate about the claims of a band of Shakespeare Birthers that the real author of the most famous plays in the world was Edward de Vere, 17th earl of Oxford. Given that Shakespeare's name appeared on numerous printed versions of his plays during his lifetime, the film should have been called "Pseudonymous." It was filled with errors about Shakespeare and Oxford, but it got at something right about authorship: It's sometimes convenient to avoid signing your name to your work.

Anonymity and pseudonymity have a long history. We think of medieval authors laboring anonymously, but even the first age of literary celebrities, the 18th century, was also paradoxically an age of anonymity. Book historian James Raven estimates that "over 80 percent of all novels published in Britain between 1750 and 1790 were published anonymously." Given that only Henry Fielding (best known for "Tom Jones") of the major 18th century novelists put his name on the title page, we ought to think of anonymity as the default position for the novel, thought to be a low form.

Satirists such as Jonathan Swift and Alexander Pope published anonymously, often for legal and political reasons. Anonymity protected Swift from arrest when a reward was offered for the author of his "Drapier's Letters," pamphlets advising the Irish not to take copper half-pence from England. The novels of Daniel Defoe, Samuel Richardson, Laurence Sterne, Tobias Smollett and Fanny Burney were all anonymous. Defoe's fictions were even putatively authored by their main characters: Robinson Crusoe, Moll Flanders, Roxana. (He was probably writing counterfeit autobiographies, not novels.)

Oliver Goldsmith comically presented some problems of the author that anonymity entailed in the preface to his "Essays" (1765): "I have seen some of my labours sixteen times reprinted, and claimed by different parents. ... These gentlemen have kindly stood sponsors to my productions, and to flatter me more, have always past them as their own."

Journalism too was generally anonymous. Joseph Addison and Richard Steele were "Mr. Spectator" with an initial at the end of each daily Spectator essay providing a clue to the author's identity.

Samuel Johnson, the subject of the world's most famous literary biography, is far from unknown to literary history, yet until he was nearly 40, his name only appeared on a handful of his writings. And even after his "Dictionary of the English Language" was published with his name in 1755, he often remained anonymous. Johnson wrote to the printer of "Rasselas," his only long fiction, "I will not print my name, but expect it to be known." Printers and booksellers would be in the know; readers familiar with his style would guess.

Johnson once responded in his "Rambler" to a letter seeking his identity by relaying "the answer of a philosopher to a man, who, meeting him in the street, desired to see what he carried under his cloak; 'I carry it there,' says he, 'that you may not see it.'"

Samuel Richardson wrote to the publisher of Johnson's anonymous "Rambler" essays, Edward Cave, "The author I can only guess at. There is but one man, I think, that could write them; I desire not to know his name; but I should rejoice to hear that they succeed." Cave wrote back, "Mr. Johnson is the Great Rambler, being, as you observe, the only man who can furnish two such papers in a week, besides his other great business."

Making slow progress on his dictionary, worried about the discrepancy between his own morality and that which he advised, Johnson had his reasons for anonymity.

Among the Romantics, Sir Walter Scott as novelist was called the Great Unknown in reviews. In fact, assigning a range of his copyrights to Archibald Constable in 1820, Scott insisted on a clause stipulating that if his publisher divulged his name as the author of the Waverley novels, he would pay Scott 2,000 pounds.

Six years earlier a provincial English author writing from the village of Chawton to a relative claimed, "Walter Scott has no business to write novels, especially good ones — it is not fair. — He has fame and profit enough as a Poet, and should not be taking the bread out of other people's mouths. — I do not like him, & do not mean to like Waverley if I can help it — but fear I must."

Scott was indemnified, as Jane Austen's letter makes clear, against the voicing of an open secret. And her joke was right on target: In a letter of the time, Scott said: "Many things would please people well enough anonymously, which, if they bore me on the title-page, would just give me that sort of ill-name which precedes hanging, and that would be in many respects inconvenient if I thought of again trying a grande opus." When he officially revealed himself in 1827 he called anonymity "the humour or caprice of the time."

Austen was herself the hidden author of "Sense and Sensibility," ("by a Lady"); "Pride and Prejudice" ("by the author of 'Sense and Sensibility'") and "Emma," ("by the author of 'Pride and Prejudice'"). Robert Griffin, who publishes on anonymity, says his favorite marketing formula of this sort is "'Discipline' by the author of 'Self-Control.'"

Men wrote some books "by a lady," and the Victorian-era cases of George Eliot (Mary Ann Evans) and the Bell brothers — that is, the Bronte sisters — remind us that the situation is reversible. Perhaps the question of anonymity should be turned on its head, and we should ask rather why any authors ever signed their names to books in those days.

But with success male authors, and some women, began to reveal their identities in the Victorian period. Charles Dickens was "Boz" until "The Pickwick Papers" (1837). Some Victorian novelists, such as Anthony Trollope, used their real names from the outset.

In the 20th century, anonymity and pseudonymity are hardly about genteel modesty. When the new editor of the Times (of London) Literary Supplement, John Gross, announced in 1974 that the TLS book reviewers' masks would come off, it was a major cultural moment. I wrote in support, and he replied that he was "in need of every drop of encouragement" he could get because the "old guard" was protesting his change. There had been some self-reviewing (a practice of two centuries in Britain), some especially generous reviewing of friends and much malign reviewing of enemies. But after Gross changed the policy, one could no longer write a savage review of a book in TLS under the cloak of anonymity and privately commiserate with the author of it.

Some popular and highly regarded novelists today try to see if their fans' love extends beyond their personal brands by employing pseudonyms, and some compartmentalizing professors use them for mysteries. But it is the unusual contemporary novel that appears anonymously. Think of such novels as Joe Klein's thinly disguised portrayal of Bill Clinton, "Primary Colors," or the mean-spirited fiction "O" by John McCain's sore-loser strategist, Mark Salter.

Online, "nym wars" have erupted over the right to false identities on social media sites. A Syrian lesbian blogging on the "Arab Spring" turned out to be a middle-aged white man at Edinburgh University. And a shifting international flash mob of hacktivists, who briefly unite electronically for acts of civil disobedience, employ the most famous name of all unknown writers, Anonymous.

Robert Folkenflik, emeritus professor of English at UC Irvine, specializes in 18th century literature and Samuel Johnson. He wrote this for the Los Angeles Times.