WASHINGTON—A group of leading historians held a press conference Monday at the National Geographic Society to announce they had "entirely fabricated" ancient Greece, a culture long thought to be the intellectual basis of Western civilization.

The group acknowledged that the idea of a sophisticated, flourishing society existing in Greece more than two millennia ago was a complete fiction created by a team of some two dozen historians, anthropologists, and classicists who worked nonstop between 1971 and 1974 to forge "Greek" documents and artifacts.

"Honestly, we never meant for things to go this far," said Professor Gene Haddlebury, who has offered to resign his position as chair of Hellenic Studies at Georgetown University. "We were young and trying to advance our careers, so we just started making things up: Homer, Aristotle, Socrates, Hippocrates, the lever and fulcrum, rhetoric, ethics, all the different kinds of columns—everything."

Just one of the "ancient" artifacts dreamed up in a basement in Somerville, MA.

"Way more stuff than any one civilization could have come up with, obviously," he added.

According to Haddlebury, the idea of inventing a wholly fraudulent ancient culture came about when he and other scholars realized they had no idea what had actually happened in Europe during the 800-year period before the Christian era.

Frustrated by the gap in the record, and finding archaeologists to be "not much help at all," they took the problem to colleagues who were then scrambling to find a way to explain where things such as astronomy, cartography, and democracy had come from.

Within hours the greatest and most influential civilization of all time was born.

"One night someone made a joke about just taking all these ideas, lumping them together, and saying the Greeks had done it all 2,000 years ago," Haddlebury said. "One thing led to another, and before you know it, we're coming up with everything from the golden ratio to the Iliad."

"That was a bitch to write, by the way," he continued, referring to the epic poem believed to have laid the foundation for the Western literary tradition. "But it seemed to catch on."

Around the same time, a curator at the Smithsonian reportedly asked for Haddlebury's help: The museum had received a sizeable donation to create an exhibit on the ancient world but "really didn't have a whole lot to put in there." The historians immediately set to work, hastily falsifying evidence of a civilization that— complete with its own poets and philosophers, gods and heroes—would eventually become the centerpiece of schoolbooks, college educations, and the entire field of the humanities.

Emily Nguyen-Whiteman, one of the young academics who "pulled a month's worth of all-nighters" working on the project, explained that the whole of ancient Greek architecture was based on buildings in Washington, D.C., including a bank across the street from the coffee shop where they met to "bat around ideas about mythology or whatever."

"We picked Greece because we figured nobody would ever go there to check it out," Nguyen-Whiteman said. "Have you ever seen the place? It's a dump. It's like an abandoned gravel pit infested with cats."

She added, "Inevitably, though, people started looking around for some of this 'ancient' stuff, and next thing I know I'm stuck in Athens all summer building a goddamn Parthenon just to cover our tracks."

Nguyen-Whiteman acknowledged she was also tasked with altering documents ranging from early Bibles to the writings of Thomas Jefferson to reflect a "Classical Greek" influence—a task that also included the creation, from scratch, of a language based on modern Greek that could pass as its ancient precursor.

Historians told reporters that some of the so-called Greek ideas were in fact borrowed from the Romans, stripped to their fundamentals, and then attributed to fictional Greek predecessors. But others they claimed as their own.

"Geometry? That was all Kevin," said Haddlebury, referring to former graduate student Kevin Davenport. "Man, that kid was on fire in those days. They teach Davenportian geometry in high schools now, though of course they call it Euclidean."

Sources confirmed that long hours and lack of sleep took their toll on Davenport, and after the lukewarm reception of his work on homoeroticism in Spartan military, he left the group.

In a statement expressing their "profound apologies" for misleading the world on the subject of antiquity for almost 40 years, the historians expressed hope that their work would survive on its own merits.

"It would be a shame to see humanity abandon achievements such as heliocentrism and the plays of Aeschylus just because of their origin," the statement read in part. "Moreover, we have some rather disappointing things to tell you about the pyramids, the works of Leonardo da Vinci, penicillin, the Internet, the scientific method, movies, and dogs."