ART REVIEW : Illuminating History’s Dark Corners : Art: ‘Mexico: Splendors of Thirty Centuries” lives up to its publicity in unexpected ways. The show opens Sunday.

‘Mexico: Splendors of Thirty Centuries” is not the same exhibition that had its debut a year ago at New York’s Metropolitan Museum of Art. It’s both more and less than that.

In its inexorable march across the continent, which included an interim visit to San Antonio, this staggering assembly of some 400 carvings, paintings and examples of the decorative arts created outsize anticipation for its glories and wariness about its politics. The show lives up to its publicity, but in unexpected ways.

Artistically, its pre-Columbian material is predictably marvelous, its modern work generally dismal. Perhaps the greatest acheivement of the show, opening Sunday at the Los Angeles County Museum of Art, has been the new prominence afforded to the art produced in the interim. A bright light has been shined into a hitherto dark hole.

Reference to Mexican art typically conjures images either pre-Columbian or Modern, from powerfully blunt ritual carvings at ancient Olmec temples to the panoramic Modern murals by los tres grandes --Jose Clemente Orozco, Diego Rivera and David Alfaro Siqueiros. Now, these are likely to be joined by Colonial images--by art executed during the 300 years after Cortes’ brutal destruction of the great Mexica (or Aztec) civilization, and before the upheavals of the 19th Century that led to the modern revolution.

At one end of this new spectrum stands a spectral, shockingly minimalist full-length portrait of a young novitiate (circa 1777), which seems conjured from 100 subtly different shades of white. An unidentified artist miraculously conveys the Catholic mystery of devotional marriage to Christ, as well as the nerve-wracking human capacity for such heady renunciation of the flesh. He deftly places the girl’s finger into the closed pages of a prayer book, which she holds at her bosom as if in effigy of the stigmata.

At the other end is the lush and aggressive Baroque spectacle of a late-17th-Century altarpiece. Its heavy encrustation of gold-leaf carving frames melodramatic paintings of the “Seven Sorrows of the Virgin.” The ensemble, here flanked by polychromed carvings of archangels from another cathedral, at least begins to suggest the near-hallucinatory heights religious artifacts could reach in such (immovable) spectacles as the Jesuit seminary at Tepotzotlan, just outside Mexico City.

In between these extremes of modesty and lavishness, the intricate threads of foreign influence on indigenous style are demonstrated by a display of decorative and secular arts. Thanks to the robust trade lines of the Manila Galleon, which linked Spain’s colony in the Philippines with its colony in the Americas, those styles trace roots to Asia as well as Europe. Most exquisitely in pottery, but in needlework as well, Chinese motifs are everywhere apparent.

The greatest loss in the exhibition comes at what should be--and was, in the New York debut--a tour de force. The moment of transition between the pre-Columbian grandeur of various Indian civilizations and the vicious colonization launched by an entrepreneur from Spain is appropriately blunt, even startling. Step across the threshhold from a gallery devoted to exquisite artifacts from Tenochtitlan, imperial capital of the Mexica, into one that heralds the arrival of Catholicism and the conquest, and the swift eradication of an entire civilization by a tiny band of Spaniards is viscerally felt.

What is not clearly seen, however, is the remarkable absorption of great Indian traditions into Spanish ones. Some pivotal works have been deleted from the tour.

Absent is a small and extraordinary mosaic of feathers fashioned as the “Mass of St. Gregory,” thus exploiting an Indian technique to render a Catholic miracle. A monumental stone cross, carved in an echo of pre-Columbian style to evoke the crucifixion, is present, but apparently couldn’t fit through museum doors; it stands outside in the courtyard.

Some objects do survive in the gallery to tell the tale, including a great silver-gilt chalice with feather-mosaic insets (it’s from LACMA’s own collection). But, gone are two large, rare, 16th-Century manuscripts and a life-size image of the Virgin of Guadalupe, made from inlaid mother-of-pearl in the late 1600s.

The absences dull this critical episode. Colonialism’s power is simply more intelligible when one confronts a cult-image of the Virgin of Guadalupe, and knows the cult was born in 1531 of a vision on the hill of Tepeyac, a pre-Hispanic shrine sacred to a mother-goddess (Tonantzin). The absorption of Indian faith into Spanish myth is crucial to understanding the nature--and the power--of the Colonial aesthetic.

The exhibition names the three centuries following the conquest the “Viceregal period,” after the ruling viceroys appointed by Spain. Usefully, the term identifies the courtly nature of the art, but it also betrays a certain nervousness. It replaces what everyone else calls Colonial--and colonialism is a highly charged subject today.

Nowhere is the triumph of colonialism clearer than in a darkly sumptuous, 10-panel folding screen attributed to Juan Correa (circa 1645-1716). One side depicts the first meeting of Cortes and Moctezuma, the other shows personifications of the four continents into which Spain had expanded its authority.

Correa has dressed the Aztec ruler as a Roman emperor. The implication of Spanish conquest as heir to the ancient Roman empire makes Moctezuma’s imminent fall sweepingly “heroic.” Meanwhile, on the reverse, the sumptuous lords and ladies of America, Asia and Africa are all given the physical features of Europeans, the benchmark being portraits of Spain’s king Charles II and his French wife, Marie-Louise d’Orleans.

You won’t find analysis of these unmistakable evocations of colonial power in the entries of the show’s otherwise useful catalogue. (The book, like the show, is immense, its 712 pages weighing in at 7 1/2 lbs.) They’re less likely to interpret meaning than to airily extoll “the splendor of the Baroque.”

This reticence has fueled the noisy charges of political manipulation that have followed “Mexico: Splendors of Thirty Centuries” on its tour. And, in fact, not since the legendary “Treasures of Tutankahmun” traveled the nation in the 1970s, in order to prepare the citizenry for a fundamental shift in hitherto strained U.S. relations with Egypt, has an art exhibition had so deep and far-reaching a political ramification as this one.

It’s too much to claim that “Splendors” has a hard agenda that can be tied to a particular government administration, past or present, in Mexico or the United States. But, as surely as art of the “Viceregal” period represents prevailing political sentiments of its time, so complex currents in our own are inevitably embodied in this officially sanctioned show.

The significance afforded to a public and environmentally scaled art--from pre-Columbian temple sites to Baroque extravaganzas to the Modern mural movement--is one central thread of 3,000 years of Mexican culture. Indeed, the artistic low-point of the show arrives in the tumultuous 19th Century, with the arrival of autonomous easel-painting.

Any exhibition of singular objects--paintings, sculptures, artifacts--is thus unavoidably fragmentary and false. You can’t send a pyramid or cathedral on the road.

But, “Splendors” makes every effort to remind the viewer of the art’s public context, through gallery photomurals and catalogue illustrations--every effort, that is, except in the case of the 20th-Century muralists. Necessarily represented in the show by easel paintings, which are rarely their great works, los tres grandes are afforded neither photomurals nor significant catalogue illustrations to illuminate the public commitments on which their principal importance rests.

So, the blockbuster ends with a whimper. Represented by easel painting, individualism and private action are held aloft on a grand foundation, built by the collective achievements of pre-Columbian and “Viceregal” forebears. This wishful thinking sharply recasts Mexico’s artistic history.

In fact, truly modern individualism is embodied in Mexican folk customs of the 19th and 20th Centuries. But arte popular is here downplayed. Rooms full of minor canvases by hack academics and pale regionalists threaten to swamp the small pictures by Hermenegildo Bustos--notably, a self-taught amateur clearly under the spell of the newly invented camera, and the one great painter of Mexico’s 19th Century. And the perfunctory inclusion of just four small ex votos --public offerings painted on tin, in heartfelt gratitude for divine intervention in temporal suffering--obscures a fundamental source for Frida Kahlo’s important Modern images.

It’s doubtful organizers would have filled the pre-Columbian galleries with second- and third-rate work, the way they have the 19th- and 20th-Century rooms, if greater art was available. But if you’re looking only for art supported by an aristocracy, and the aristocracy largely adored mediocrity, that is what you get.

“Mexico: Splendors of Thirty Centuries” is an amazing, abundant array, which will not likely come our way again anytime soon. For that reason it should be seen by anyone who cares about art and about Mexican culture. For that same reason, it should also be seen with a careful eye.

At LACMA, 5905 Wilshire Blvd., (213) 857-6000, through Dec. 29. Closed Mondays.