A post I made some years ago on another board.  Hopefully it will be of interest to the members of this site.

The Virgin of Guadalupe is the Patron Saint of Mexico (and the Continental Americas); you will find images of her throughout Mexico (and the rest of Latin America). What follows is the most common version given by devote believers of how the Virgin of Guadalupe became the Mexico’s patron saint.In 1523, just two years after the Aztec capital of Tenochitlan fell to Hernán Cortés de Monroy y Pizarro and his Conquistadors, the first Roman Catholic missionaries arrived to begin the religious conquest of Mexico.Fray Bernadino de Sahagún and his fellow Franciscans immediately immersed themselves in an intensive study of indigenous tongues along with the history, customs and religious practices of the Mexicas, whom they called Aztecs. Soon fluent in Nahuatl, they proceeded to translate religious texts and teach the Christian doctrines.Among their first converts was a man baptized with the Christian name Juan Diego. On the chilly morning of December 9, 1531, Juan Diego crossed the barren hill called Tepeyac to attend Mass. He was brought to a sudden halt by a blinding light and the sound of unearthly music. Before him appeared an astounding vision--a beautiful dark-skinned woman who, calling the Indian "my son," declared herself to be the Virgin Mary, the mother of Jesus Christ. She told Juan Diego it was her desire to have a church built on Tepeyac hill, and asked him to relay that message to Bishop Juan de Zumarraga.It was no easy task for the humble Indian to be granted an audience with the top prelate, but the persistent Juan Diego was finally admitted. The incredulous Bishop demanded that he be provided with some proof of the unlikely encounter. Confused and fearful, Juan Diego avoided Tepeyac for several days, but on December 12, while rushing to find a priest to attend a seriously ill uncle, he took a short cut across the hill. The Virgin once again appeared and Juan Diego told her of the Bishop's request. The Virgin instructed him to pick roses from the usually sere and desolate hill and deliver them to Zumarraga as the sign.Juan Diego gathered up the miraculous blossoms in his mantle and hurried off to complete his mission. Once again before the Bishop, he let the roses spill out before him. To the wonder of all assembled, a perfect image of La Virgen Morena (the Dark Virgin) was revealed emblazoned on Juan Diego's cloak.  By order of the Bishop, a small church was soon constructed on the site designated by the Virgin. Skeptics are quick to point out the unlikely coincidence of the Virgin's appearance on Tepeyac, the very site of an Aztec temple dedicated to Tonatzin (earth goddess, mother of the gods and protectress of humanity) which had been devastated by order of Bishop Zumarraga.The original church was replaced by a larger structure built in 1709. The Miracle of Guadalupe was officially recognized by the Vatican in 1745. The second sanctuary was declared a Basilica in 1904, but by then it had begun to slowly sink into the soft, sandy soil beneath it. A new Basilica, of modern design and enormous capacity, was dedicated in October of 1976.In this. and other churches, dedicated to La Virgen de Guadalupe throughout the nation, millions of the faithful will gather December 12th for processions, prayers, songs, dances, and fireworks to honor “La Reina de Mexico” (the Queen of Mexico).Juan Diego’s mantle, carefully preserved in the new Basilica, has been subjected to extensive analysis over the years. Experts have authenticated the fabric as dating to the 16th century, but have been unable to determine the type of pigment from which the image was rendered. Additionally, although centuries have passed the image of the Virgin de Guadalupe remains clearly imprinted on the cloak without visible signs of deterioration. Faithful Catholics consider this proof that the story of the Virgin of Guadalupe is true.The first extended account of the image and the apparition comes in Imagen de la Virgen Maria, Madre de Dios de Guadalupe, a guide to the cult for Spanish-speakers published in 1648 by Miguel Sanchez, a diocesan priest of Mexico City. An anonymous Nahuatl language narrative, Huei tlamhuicoltica (“The Great Event”), appeared at around the same time, probably written in 1649 by Luis Lasso de la Vega and based on Sánchez's narrative, which it closely mirrors. This contains Nican mophua (“Here it is recounted”), a tract about the Virgin which contains the story of the apparition and the supernatural origin of the image, plus two other sections, Nican motecpana (“Here is an ordered account”), describing fourteen miracles connected with Our Lady of Guadalupe, and Nican tlantica (“Here ends”), an account of the Virgin in New Spain.The growing fame of the image led to a parallel interest in Juan Diego. In 1666 the Church, with the aim of establishing a feast day in his name, began gathering information from people who had had known him, and in 1723 a formal investigation into his life was ordered, and much information was gathered. In 1987, under Pope John Paul II, who took an especial interest in saints and in non-European Catholics, the Congregation for the Causes of Saints declared him "venerable", and on May 6, 1990 he was beatified by the Pope himself during Mass at the Basilica of Our Lady of Guadalupe in Mexico City, being declared “protector and advocate of the indigenous peoples," with December 9 as his feast day.The first extended account of the image and the apparition comes in Imagen de la Virgen Maria, Madre de Dios de Guadalupe, a guide to the cult for Spanish-speakers published in 1648 by Miguel Sanchez, a diocesan priest of Mexico City. An anonymous Nahuatl language narrative, (“The Great Event”), appeared at around the same time, probably written in 1649 by Luis Lasso de la Vega and based on Sánchez's narrative, which it closely mirrors. This contains Nican mopohua (“Here it is recounted”), a tract about the Virgin which contains the story of the apparition and the supernatural origin of the image, plus two other sections, Nican motecpana (“Here is an ordered account”), describing fourteen miracles connected with Our Lady of Guadalupe, and Nican tlantica (“Here ends”), an account of the Virgin in New Spain.At this point historians and theologians began to question the quality of the evidence regarding Juan Diego. There is no mention of him or his miraculous vision in the writings of bishop Zumárraga, into whose hands he delivered the miraculous image, nor in the record of the ecclesiastic inquiry of 1556, which omits him entirely, nor anywhere else before the mid-17th century. Doubts as to his reality were not new: in 1883 Joaquin Garcia Icabalaecta, historian and biographer of Zumárraga, in a confidential report on the Lady of Guadalupe for Bishop Labastida, was very hesitant to support the story of the apparition and stated his conclusion that there was never such a person. Neither were they welcome: in 1897 the Bishop of Tamaulipas, Eduardo Sánchez Camacho, was forced to leave his post after expressing similar disbelief, and as recently as 1996 the abbot of the Basilica of Guadalupe, Guillermo Schulenburg, was forced to resign following an interview with the Catholic magazine Ixthus, when he said that Juan Diego was “a symbol, not a reality.”In 1995, with progress towards sanctification at a stand-still, Father Xavier Escalada, a Jesuit writing an encyclopedia of the Guadalupan legend, produced a deer skin codex, (Codex Escalada), illustrating the apparition and the life and death of Juan Diego. Although the very existence of this important document had been previously unknown, it bore the date 1548, placing it within the lifetime of those who had known Juan Diego, and bore the signatures of two trustworthy 16th century scholar-priests, Antonio Valeriano and Bernardino de Sahagún, thus verifying its contents. Some scholars remained unconvinced, describing the discovery of the Codex as "rather like finding a picture of St. Paul's vision of Christ on the road to Damascus, drawn by St. Luke and signed by St. Peter", but Diego was declared a saint, with the name of Saint Juan Diego Cuauhtlatoatzin, in 2002.The following , ‘Miraculous’ Image of Guadalupe by Joe Nickell (June 2002) is found on the website of the Committee for the Scientific Investigation of Claims of the Paranormal at http://www.csicop.or...e_of_guadalupe/ as accessed on September 2006: Mexico’s Image of Guadalupe is a sixteenth-century depiction of the Virgin Mary that, according to pious legend, she imprinted miraculously on an Aztec convert’s cloak. The Indian, Juan Diego, is expected to be canonized as a saint, although new evidence confirms skeptics’ claims that the image is merely a native artist”s painting, the tale apocryphal, and “Juan Diego” probably fictitious. The story of Juan Diego is related in the Nican Mopohua ("an account") written in the native Aztec language and sometimes called the “gospel of Guadalupe.” According to this account, in early December of 1531 (some ten years after Cortez's defeat of the Aztec Empire) Juan Diego was a recent convert who supposedly left his village to attend Mass in another. As he passed the foot of a hill named Tepeyac he encountered a young girl, radiant in golden mist, who identified herself as “the ever-virgin Holy Mary, mother of the true God” and asked that a temple be built on the site. Later, as a sign to a skeptical bishop, she caused her self- portrait to appear miraculously on Juan's cactus-fiber cloak. The legend obviously contains a number of motifs from the Old and New Testament as well as statements of specific Catholic dogma. Indeed, the tale itself appears to have been borrowed from an earlier Spanish legend in which the Virgin appeared to a shepherd and led him to discover a statue of her along a river known as Guadalupe ("hidden channel"). Moreover, the resulting shrine at Tepeyac was in front of the site where the Aztecs had had a temple for their own Virgin goddess Tonantzin (Smith 1983). Thus the Catholic tradition was grafted onto the Indian one, a process folklorists call syncretism. The image itself also yields evidence of considerable borrowing. It is a traditional portrait of Mary, replete with standard artistic motifs and in fact clearly derived from earlier Spanish paintings. Yet some proponents of the image have suggested that the obvious artistic elements were later additions and that the "original" portions-the face, hands, robe, and mantle-are therefore "inexplicable" and even "miraculous" (Callahan 1981). Actually, infrared photographs show that the hands have been modified, and close-up photography shows that pigment has been applied to the highlight areas of the face sufficiently heavily so as to obscure the texture of the cloth. There is also obvious cracking and flaking of paint all along a vertical seam, and the infrared photos reveal in the robe's fold what appear to be sketch lines, suggesting that an artist roughed out the figure before painting it. Portrait artist Glenn Taylor has pointed out that the part in the Virgin's hair is off-center; that her eyes, including the irises, have outlines, as they often do in paintings, but not in nature, and that these outlines appear to have been done with a brush; and that much other evidence suggests the picture was probably copied by an inexpert artist from an expertly done original. In fact, during a formal investigation of the cloth in 1556, it was stated that the image was “painted yesteryear by an Indian,” specifically “the Indian painter Marcos.” This was probably the Aztec painter Marcos Cipac de Aquino who was active in Mexico at the time the Image of Guadalupe appeared. In 1985, forensic analyst John F. Fischer and I reported all of this evidence and more in “a folkloristic and iconographic investigation” of the Image of Guadalupe in Skeptical Inquirer. We also addressed some of the pseudoscience that the image has attracted. (For example, some claim to have discovered faces, including that of “Juan Diego” in the magnified weave of the Virgin's eyes-evidence of nothing more than the pious imagination's ability to perceive images, inkblot-like, in random shapes) (Nickell and Fischer 1985). Recently our findings were confirmed when the Spanish-language magazine Proceso reported the results of a secret study of the Image of Guadalupe. It had been conducted - secretly - in 1982 by art restoration expert José Sol Rosale. Rosales who examined the cloth with a stereomicroscope and observed that the canvas appeared to be a mixture of linen and hemp or cactus fiber. It had been prepared with a brush coat of white primer (calcium sulfate), and the image was then rendered in distemper (i.e., paint consisting of pigment, water, and a binding medium). The artist used a “very limited palette,” the expert stated, consisting of black (from pine soot), white, blue, green, various earth colors (“tierras”), reds (including carmine), and gold. Rosales concluded that the image did not originate supernaturally but was instead the work of an artist who used the materials and methods of the sixteenth century (El Vaticano 2002). In addition, new scholarship (e.g. Brading 2001) suggests that, while the image was painted not long after the Spanish conquest and was alleged to have miraculous powers, the pious legend of Mary's appearance to Juan Diego may date from the following century. Some Catholic scholars, including the former curator of the basilica Monsignor Guillermo Schulemburg, even doubt the historical existence of Juan Diego. Schulemburg said the canonization of Juan Diego would be the "recognition of a cult" (Nickell 1997). However, the skeptics are apparently having little if any effect and Juan Diego" is as popular among Catholics as he is, apparently, fictitious. On July 31, 2002, the Pope canonized Juan Diego before a crowd of 12 million, and later that year included in the General Calendar the liturgical celebrations of Saint Juan Diego Cuauhtlatoatzin (December 9) and Our Lady of Guadalupe (December 12) The Wikipeida article “Our Lady of Gudalupe” under the sub-heading “Scientific Analysis” says:In 1979 Philip Serna Callahan investigated the composition of the image through infrared photography (used to detect sub-surface layers not visible to the naked eye). He identified the moon, sun-rays and sash, stars and nahui olin, among other elements, as standard "International Gothic" additions, possibly from the second half of the 16th century. The original image beneath these, namely the hands, face, blue mantle and rose-coloured robe, showed no underdrawing, sizing or overvarnish.In 1999 Leoncio Garza-Valdés of the University of Texas at San Antonio was engaged by the Archbishop of Mexico, Norberto Rivera Carrera, to undertaken a scientific study of the image using ultra-violet imaging. Garza-Valdés' findings contradicted those by Callahan, finding three distinct layers involving all areas of the image, including those Callahan had identified as original. The oldest image, with striking similarities to the Spanish Lady of Guadalupe of Extremadura, shows a light-skinned Virgin carrying a child on her left arm. This layer bears the signature M.A. and the date 1556. A second Virgin has been painted over the first, and shows facial features of strong native American type. This second Virgin was probably painted by Juan de Arrue around 1625. The third image, the one currently visible, is painted 15 cm to the left of the second. Sample fibres given to Garza-Valdés proved to be of hemp and linen, not agave.The painting was examined again in 2002 by art restoration expert José Sol Rosales with stereo-microscopy (a technique used to identify pigments and the integrity of images). Rosales identified calcium sulfate, pine soot, white, blue, and green "tierras" (soil), reds made from carmine and other pigments, as well as gold, all consistent with 16th century materials and methods. Despite Callahan's conclusion that the hands, face, mantle and robe could be identified as "original" and have never been painted, pigment has been applied to the highlight areas of the face sufficiently heavily as to obscure the texture of the underlying cloth, while the parting in the Virgin's hair is off-center, and her eyes, including the irises, have outlines, apparently applied by a brush; in addition there is obvious cracking and flaking of paint all along a vertical seam, and, in the robe's fold, what appear to be sketch lines, suggesting that the artist roughed out the figure before painting it.The religious and cultural impact of the Virgin of Guadalupe is enormous. The shrine of the Virgin of Guadalupe is the most visited Catholic pilgrimage destination in the world. Over the Friday and Saturday of 11 to 12 December 2009, a record number of 6.1 million pilgrims visited the Basilica of Guadalupe in Mexico City to commemorate the anniversary of the apparition.The Virgin of Guadalupe is considered the Patroness of Mexico and the Continental Americas; she is also venerated by Native Americans, on the account of the devotion calling for the conversion of the Americas. Replicas of the tilma can be found in thousands of churches throughout the world, and numerous parishes bear her name.