A modern folklorist's professional definition of legend was proposed by Timothy R. Tangherlini in 1990:
Legend, typically, is a short (mono-) episodic, traditional, highly ecotypified historicized narrative performed in a conversational mode, reflecting on a psychological level a symbolic representation of folk belief and collective experiences and serving as a reaffirmation of commonly held values of the group to whose tradition it belongs."
The word "legend" appeared in the English language circa 1340, transmitted from medieval Latin language through French. Its blurred extended (and essentially Protestant) sense of a non-historical narrative or myth was first recorded in 1613. By emphasizing the unrealistic character of "legends" of the saints, English-speaking Protestants were able to introduce a note of contrast to the "real" saints and martyrs of the Reformation, whose authentic narratives could be found in Foxe's Book of Martyrs. Thus "legend" gained its modern connotations of "undocumented" and "spurious".
Before the invention of the printing press, stories were passed on via oral tradition. Storytellers learned their stock in trade: their stories, typically received from an older storyteller, who might, though more likely not, have claimed to have actually known a witness, rendered the narrative as "history". Legend is distinguished from the genre of chronicle by the fact that legends apply structures that reveal a moral definition to events, providing meaning that lifts them above the repetitions and constraints of average human lives and giving them a universality that makes them worth repeating through many generations. In German-speaking and northern European countries, "legend", which involves Christian origins, is distinguished from "Saga", being from any other (usually, but not necessarily older) origin.
The modern characterisation of what may be termed a "legend" may be said to begin in 1865 with Jacob Grimm's observation, "The fairy tale is poetic, legend, historic. Early scholars like Karl Wehrhahn Friedrich Ranke and Will-Erich Peukert followed Grimm's example in focussing solely on the literary narrative, an approach that was enriched particularly after the 1960s by addressing questions of performance and the anthropological and psychological insights provided in considering legends' social context. Questions of categorizing legends, in hopes of compiling a content-based series of categories on the line of the Aarne-Thompson folktale index provoked a search for a broader new synthesis.
Compared to the highly-structured folktale, legend is comparatively formless, Helmut de Boor noted in 1928. The narrative content of legend is in realistic mode, rather than the wry irony of folktale; Wilhelm Heiske remarked on the similarity of motifs in legend and folktale and concluded that, in spite of its realistic mode, legend is not more historical than folktale.
Legend is often considered in connection with rumour, also believable and concentrating on a single episode. Ernst Bernheim suggested that legend is simply the survival of rumour. Gordon Allport credited the staying-power of certain rumours to the persistent cultural state-of-mind that they embody and capsulise; thus "Urban legends" are a feature of rumour. When Willian Jansen suggested that legends that disappear quickly were "short-term legends" and the persistent ones be termed "long-term legends", the distinction between legend and rumour was effectively obliterated, Tangherlini concluded.
The elasticity of legend in its highly specific and localised social context has rendered it elusive to attempts to typify it simply through its content, as fairy tales have been successfully categorised.
Modern retellings of the legend of Saint George omit many of the miraculous happenings that were central to earlier versions, but which have lost credibility. Thus modern "urban legends" are quite correctly termed legends: "it happened to the brother-in-law of someone my friend's mother knew". In short, legends are believable, although not necessarily believed. For the purpose of the study of legends, in the academic discipline of folkloristics, the truth value of legends is irrelevant because, whether the story told is true or not, the fact that the story is being told at all allows scholars to use it as commentary upon the cultures that produce or circulate the legends.
Hippolyte Delehaye, (in his Preface to The Legends of the Saints: An Introduction to Hagiography, 1907) distinguished legend from myth: "The legend, on the other hand, has, of necessity, some historical or topographical connection. It refers imaginary events to some real personage, or it localizes romantic stories in some definite spot."
A clear example, which distinguishes what is myth from what is legend, is the story of the Gordian Knot. The legend concerns Alexander the Great, who, when confronted with the ancient knot of cornel bark that secured the pole of the sacral ox-cart at Gordium in the winter of 333 BC, severed it with a slash of his sword. The myth of the Gordian Knot is the founding myth of Gordium itself, justifying the authenticity of its line of kings.
From the moment a legend is retailed as a legend, its authentic legendary qualities begin to fade and recede: in The Legend of Sleepy Hollow, Washington Irving transformed a local Hudson River Valley legend into a literary anecdote with "Gothic" overtones, which actually tended to diminish its character as genuine legend. Like metaphors, legends may be living or dead: the vital signs of a legend depend upon its being fiercely defended as true, such as the voyage of Brendan or the Black Legend of the supposedly fanatical and cruel national character of Spain.
Legend may be transmitted orally, passed on person-to-person, or, in the original sense, through written text. Jacob de Voragine's Legenda Aurea or "The Golden Legend" comprises a series of vitae or instructive biographical narratives, tied to the liturgical calendar of the Roman Catholic Church. They are presented as lives of the saints, but the profusion of miraculous happenings and above all their uncritical context are characteristics of hagiography. The Legenda was intended to inspire extemporized homilies and sermons appropriate to the saint of the day.
Legend may be interpreted for its ontological consequences and be treated as myth. To take an example, myths surrounding Cadmus, a Phoenician immigrant credited with bringing the alphabet and other Near Eastern culture to Bronze Age Greece, may have begun as a series of legends gathering around the memory of the historical founder of certain coastal cities in Greece. Explaining the origins of myth as former historical legends in this fashion is termed "euhemerism". See the entry Euhemerus for more detail.
Conspiracy theories are similar to legends in that the linchpin of the conspiracy is usually a plausible, but unprovable secret agenda which exclusively drives the story and links otherwise unconnected happenings into a satisfying pattern: thus meaning is supplied for events.