Spain has sometimes been slow to recognize its own treasures. Miguel de Cervantes was slipping into obscurity after his death until he was rescued by foreign literary experts. El Greco's paintings were pulled from oblivion by the French. The Muslim palace of Alhambra had fallen into neglect before the American author Washington Irving and others wrote about it in the 1800s.
Now, more than 500 years after expelling its Jews and moving to hide if not eradicate all traces of their existence, Spain has begun rediscovering the Jewish culture that thrived here for centuries and that scholars say functioned as a second Jerusalem during the Middle Ages.
"We've gone from a period of pillaging the Jews and then suppressing and ignoring their patrimony to a period of rising curiosity and fascination," said Ana María López, the director of the Sephardic Museum in Toledo, a hub of Jewish life before the Jews were expelled or forced to convert to Christianity in 1492 during the Inquisition.
Cities and towns across Spain are searching for the remains of their medieval synagogues, excavating old Jewish neighborhoods and trying to identify Jewish cemeteries. Scholars say they are overwhelmed with requests from local governments to study archaeological findings and ancient documents that may validate a region's Jewish heritage.
Other people are joining in, delving into family histories to hunt for signs of Jewish ancestry.
"I don't go a week without someone calling and asking me if their last name has Jewish roots," said Javier Castaño, an expert in Spain's Jewish history at the Higher Council for Scientific Research in Madrid.
"It's the opposite of 300 years ago, when people changed their last names to Spanish names and looked for ancestors of pure Spanish blood," he said. "Now it's trendy to say you have Jewish roots."
But Castaño and other scholars say the revival has in some ways gone too far. They contend that some local governments, eager to attract well-heeled tourists from the United States and Israel, are making claims about their Jewish heritage that are not supported by historical evidence.
"This whole revival is a very important and positive contribution," Castaño said. "The problem is that in some cases people are falsifying the past by creating a Jewish patrimony that never existed." He and other critics say cities are promoting old Jewish quarters with no original structures, cemeteries whose real location is still a mystery and medieval synagogues that are hardly medieval, if they ever functioned as synagogues at all.
"History is being exploited," Castaño said, citing Oviedo near the northern coast and Jaén in the south as particularly egregious examples. "People are trying to reproduce what has occurred in Toledo. Everyone wants their medieval synagogue."
Toledo, with two intact medieval synagogues, including the Tránsito Synagogue from the 14th century, is something of an exception in Spain, where the expulsion of the Jews was followed by a campaign to destroy, disassemble or obscure obvious reminders of their presence.
The Network of Jewish Quarters in Spain, which works to revive and promote medieval Jewish neighborhoods, concedes that some cities have oversold their possessions.
"But it's not that they don't have the history, it's that the history is not so visible," said Assumpció Hosta, the network's secretary-general. "We have to give these cities time to invest in the recovery of their patrimony."
Spain had the most vibrant Jewish population in Europe before the expulsion of 1492, and it produced one of the most influential cultural legacies in Jewish history.
It was here that Hebrew was reborn as a language suitable not just for prayer and liturgy but for poetry and other secular pursuits, contributing to the advent in Spain of what has been called a golden age of Jewish literature, philosophy and science in the 10th and 11th centuries.
"In the minds of her sons and daughters, Sepharad was a second Jerusalem," Jane Gerber wrote in her book "The Jews of Spain: A History of the Sephardic Experience."
"Expulsion from Spain, therefore, was as keenly lamented as exile from the Holy Land," she said.
Scholarly interest in this chapter of Jewish history has been intensifying in Spain for decades, but only recently has it extended to the public.
Besides the revival of Jewish neighborhoods, there has been an explosion of books on Jewish themes, with 200 to 250 published every year, and new museums, cultural centers, restaurants and musical groups devoted to Sephardic traditions.
Medieval festivals that have typically included only Muslims and Christians are now seeking to add Jewish participants. Jewish leaders say the trend has received an added push from Prime Minister José Luis Rodríguez Zapatero, who has made encouraging a more open and tolerant society a primary objective of his administration.
Still, despite the new enthusiasm for Spain's Jewish heritage, intolerance toward Jews here is far from a thing of the past, the leaders say.
"A contradictory element in all this is that a new anti-Semitism is also developing in Spain," said Jacobo Israel Garzón, the president of the Federation of Jewish Communities in Spain. "It uses the Israeli-Palestinian conflict as its source, but it passes very quickly from anti-Israelism to anti-Semitism."
Israel said the number of Jews in Spain today was small, 40,000 to 50,000. But he said the population was growing steadily thanks to immigration, particularly from North Africa, where so many Jews fled after the 15th- century expulsion.
Many of these returnees still speak a form of the Judeo-Spanish language of their ancestors and have maintained their traditions.
"There is tremendous nostalgia for Sephardic Spain in the Jewish world, particularly in the ancestors of the expelled Jews," Israel said. "But even in the souls of the Jews who were not expelled, there is the sense that with the end of Jewish Spain something very important was lost."
"Spain is now opening the way for the study of that lost footprint," he said.