At some point, Leonardo Patterson stopped counting. He no longer knows how often they turned up at his Munich apartment: customs agents, tax officials and investigators with the state criminal police office. They became familiar with every nook and cranny of his two-room apartment in a residential tower just northeast of the city center: the small stone altar with the gold cross and prayer books; the dark oil painting above his bed, portraying a bare Jesus being flagellated by two men; the keepsake photo with the pope; the Mayan heads on his desk.

Patterson's defense attorney also cannot say how often they were there. Once a year, he estimates, like close acquaintances who wanted to drop by for a visit. Just that they carried a search warrant with them each time. "Oh, Mr. Patterson," they would say, "you've rearranged things." They would then pack the evidence they needed into their moving cartons.

Originally from Costa Rica, Patterson has been trading in ancient art for half a century. He is now turning 74, but the authorities are still after him. First it was the FBI, then Scotland Yard and finally the Spanish, the Peruvians, the Mexicans, the Guatemalans and, of course, the Germans. In London, they once confiscated a Peruvian gold mask from him; and in Munich, he is now being forced to hand over two ancient wooden heads from Mexico, provided the court ruling is upheld. But that's it. Not a good result for the authorities: maximum effort for minimal returns.

People like Patterson are euphemistically known as antiquities traders. But with a business model that is only half legal at best, the term dealer might be more accurate -- even if it is often difficult to prove wrongdoing. They profit from the fact that the immense market for archeological objects is split. On the one hand are the source countries, which are mostly poor and have passed laws against taking ancient objects out of the country -- but they often don't have the wherewithal to enforce the bans.

On the other hand are the rich countries where the collectors live. They could take action to stop the plundering, but they don't often do so. There simply isn't enough political pressure. After all, it isn't their cultural heritage that is being exploited. And the unappetizing elements of the business -- grave robbing and smuggling -- aren't taking place close to home.

Plenty of Contacts

Men like Patterson profit from the Janus-faced nature of the antiquities market. Those who manage to bring their goods out of the shadows and into the light of quasi-legality can make significant profits. And for decades, Patterson was one of the industry's biggest players. Those in New York, Sydney, Paris, Geneva or Munich who were interested in pre-Columbian art could hardly bypass the Costa Rican. Mayan skulls, ceramic warrior figures from Jalisco, smiling clay figures from the Totonac culture or a stone jaguar with an erect penis from Xochipala: He had everything on offer.

Patterson also had plenty of contacts. He knew several politicians in Costa Rica, including the foreign minister and president. And the people he knew were likewise well connected. At the end of this chain of contacts was often a collector, sometimes a counterfeiter and frequently it was just a few villagers who plundered hidden temple sites in the jungles of Central America in the hopes of making a few bucks -- so that a cultivated European in Basel or Düsseldorf could place a stone, Aztec rattlesnake on the mantelpiece.

The German government's culture commissioner, Monika Grütters, would like to take action to finally curtail the illegal trade in antiquities. She has presented a new, more stringent draft law for consideration, but resistance to the new regulation has been severe.

At a hearing on Wednesday, 14 experts were invited to speak to the Cultural and Media Affairs Committee in the German parliament, where divisions over the proposed legislation were aired. Some described it as being "good, necessary and overdue," but others warned the new due diligence requirements for dealers would be "untenable." Meanwhile, Dorothee Hansen of the Kunsthalle Bremen museum warned that "there is considerable uncertainty on the part of collectors. Many are no longer prepared to loan their works to us."

Should it ultimately pass, the new law would make it illegal in Germany to trade in artifacts that do not have an export license from their country of origin. Restitutions are also to be made easier.

Videos from the Syrian city of Palmyra, the home of ancient ruins that was occupied until recently by Islamic State, along with images from plundered archeological digs in Iraq, Afghanistan and Mali, have shifted public perception of the problem. It has now become clear to many that the issue is not merely one that affects the countries involved. Rather, the global market in stolen antiquities threatens the cultural heritage of humanity as a whole.

Archeological art differs from more recent works of art on one decisive point: The expressiveness of an historical artifact can only fully be realized if it is known where and how it was found. Should that context be removed by way of illegal excavation, the object becomes little more than decoration. Such pieces may be nice to look at, but they have very little historical value.

The illegal trade in antiquities is almost as lucrative as the illegal trade in drugs and arms, and almost as clandestine. It is currently a booming business in the war zones of the Middle East and North Africa, but almost nothing is known about the key figures involved. And even if they are identified, they don't talk.

But regardless of whether the illegal object comes from Syria, China or Costa Rica, the business is largely the same everywhere. A Central America veteran like Leonardo Patterson operates according to similar market laws as does a Turkish dealer who trades in cuneiform writing tablets from Iraq.

SPIEGEL spent recent months combing through German and Spanish court files and documents and interviewing investigators and art appraisers along with business partners, acquaintances and relatives of Patterson. We also sat down for several interviews with Patterson himself. The result is a detailed look into an astounding career. It clearly shows how Germany and other countries have thus far failed to block the trade in plundered cultural artifacts -- and why Patterson will likely be able to continue selling those objects that remain in his possession.

THE RISE

Patterson's golden age was in the 1990s. He lived at the time in Munich, where he was chauffeured around the city in a blue Rolls Royce. He even had his own polo team, including four players and 12 horses. "I was doing well at the time because I had good stuff," he says. "Good stuff" is Patterson's code for illegal objects.

Breathing heavily, he is sitting in front of his venison goulash in a restaurant in Munich's Arabellapark -- an amicable older man in a tie, blazer and jogging shoes. He is an easy man to underestimate, which is part of his secret to success. How can you not trust a man who talks quietly, stutters and has trouble finding his words? Having never learned German, Patterson speaks the mumbled Rastafari English of his Caribbean home.

In our first meeting, he was reserved, speaking vaguely of shamans, Mayan ghosts and toad poison. It was impossible to get a precise statement out of him. But on this winter day in Munich, he is transformed. His apparent naiveté from our first meeting has vanished completely and he speaks clearly for three-and-a-half hours.

For decades, Patterson's business worked as follows: His Mexican middlemen would travel to Munich on a regular basis. "They worked together with the illegal excavators," he says. "Their focus was on fresh goods, primarily because of the prices. They had to know where digging was currently going on. They always got it at the place where it was found. They knew the people in the villages."

The Mexicans knew the kinds of things that Patterson liked. They would send him photos from the excavation sites and he would choose the objects he wanted. "My people brought me the stuff to wherever I wanted it," he says. "If I was in China, they found a way to bring it there. If I was in Paris, then they brought the stuff to Paris."

Starting at the Bottom

So the Mexicans took care of the smuggling? "Yes," says Patterson, "they knew how to do it. That was how they made money. They have contacts, friends." Did they also pay bribes? "That's how they do it."

Patterson himself denies having been directly involved in smuggling. And what about the incident at the Frankfurt Airport in 2004 when, after receiving a tip, customs officials set their sights on an air freight delivery containing archeological artifacts from Mexico and simply waited until Patterson's daughter showed up? "Oh yeah," he says. "Frankfurt was an exception."

Patterson's climb to become one of the most successful dealers in Central American antiquities began at the very bottom. The son of poor Jamaican immigrants, he was born in Costa Rica in 1942. By the time he was 12, he was already working as a cook in his aunt's restaurant. Later, he was hired by a jeweler in the capital of San José. Occasionally, plunderers would come by to melt down gold. At some point, they dragged him along into the jungle to take a look at the old graves.

Patterson saw the business potential. "I wondered why I should be melting these old things down to make a terrible ring out of them," he says, and he found a dealer who would buy the original items for a higher price. It was the beginning of an astonishing career. He moved to Miami and, not long later, to New York.

There, he was taken under the wing of Everett Rassiga, the legendary gallery owner who once had an airstrip cut into the jungles of Campeche in southeastern Mexico to fly out a plundered Mayan fresco. Rassiga invited his new protégé to Mexico. "That's how I began trading in Mexican stuff," Patterson says. He started off by selling Rassiga's objects, but he soon had his own sources who would bring him fresh goods from the ancient burial plots of Central America.

A High Profile

In the 1970s, UNESCO passed a convention aimed at stopping the illegal trade of cultural artifacts, but many countries failed to immediately ratify the agreement. In the 1960s and '70s, hardly anyone in the rich countries where the collectors lived cared if huge numbers of archeological objects from illicit digs were making their way from the poor south to the prosperous north.

Patterson profited from this lawlessness and he knew how to impress his clients. He needed a high profile and, as a black man who hung out with the most exclusive gallery owners in the city, he was able to easily establish one. He would wear elegantly tailored three-piece suits when visiting the exclusive Studio 54 club in New York. And he had a former racecar driver repair his red Ferrari -- and left the workshop with an old Rolls Royce Phantom II.

Patterson had no gallery of his own, instead entertaining the rich and beautiful in the city's most expensive restaurants and showing them his pieces there. He sold some of them for a few thousand dollars, but asked millions for others. His competitors whispered that he also sold counterfeits, but Patterson responded by saying they were merely jealous of his excellent connections.

Yet counterfeits are everywhere on the antiquities market. Experts estimate that fully half of the objects on offer are fakes. There is simply no way for the illegal diggers to loot enough pieces fast enough to satisfy the demand. And despite his denials -- which he repeats to this very day -- Patterson gained a reputation for trading in counterfeits.

He moved to Los Angeles, and when he visited New York, he would stay at the luxurious St. Regis Hotel on Fifth Avenue. That's where he first met the surrealist painter Salvador Dalí. The eccentric Spaniard spent winters together with his wife Gala and ocelot Babou in room 1610, two floors above Patterson.