Mu is a lost continent first suggested by Augustus Le Plongeon (1825–1908), who connected the "Land of Mu" to the story of Atlantis. Later, James Churchward (1851–1936) linked the name Mu to the imagined land of Lemuria, claiming it once existed in the Pacific Ocean before being destroyed. The role of Mu in unscientific ideas and fictional stories is explored in detail in the book Lost Continents (1954, 1970) by L. Sprague de Camp.

Geologists explain that Mu and the lost continent of Atlantis are not real. They argue that continents cannot sink or be destroyed quickly, as described in legends, folklore, and stories about these places. There is no scientific evidence to support their existence.

History of the concept

The idea of the "Land of Mu" first appeared in the writings of Augustus Le Plongeon, a British-American researcher who studied ancient Maya ruins in Yucatán. He claimed to have translated the Popol Vuh, a sacred book of the K'iche' people, from ancient Mayan using Spanish. Le Plongeon believed the Yucatán civilization was older than those of Greece and Egypt and suggested there was an even older continent.

Le Plongeon got the name "Mu" from Charles Étienne Brasseur de Bourbourg, who in 1864 misread the Troano Codex (now called the Madrid Codex) using the de Landa alphabet. Brasseur thought a word he read as "Mu" referred to a land that had been swallowed by a disaster. Le Plongeon connected this lost land to Atlantis and, following Ignatius Donnelly’s book Atlantis: The Antediluvian World (1882), described it as a continent that once existed in the Atlantic Ocean.

Later, Mu was also called Lemuria, a hypothetical land believed to be the origin of lemurs. James Churchward popularized Mu in books like Lost Continent of Mu, the Motherland of Man (1926) and The Lost Continent Mu (1931). Churchward claimed he met a temple priest in India who showed him ancient clay tablets written in a lost language called "Naga-Maya." Churchward promised to protect the tablets and learned to read them. He said the tablets described the creation of Earth, Mu, and a civilization called Naacal, which he claimed was more advanced than modern societies.

Churchward described Mu as a large landmass in the Pacific Ocean, stretching from the Marianas to Easter Island and from Hawaii to Mangaia. He said Mu was flat with plains, rivers, and hills, and that it sank suddenly due to volcanic explosions. Churchward believed Mu was the source of ancient civilizations in Egypt, Greece, Central America, India, and others. He pointed to symbols of the sun found in many cultures as evidence, linking them to the Egyptian god Ra and the Rapa Nui word "ra'a."

Churchward also claimed that the Polynesian people were not descendants of Mu’s main civilization but of survivors who later adopted practices like cannibalism. He described structures like the stone hats on Easter Island’s moai statues as representations of the sun. Churchward said the statues’ platforms were meant to be moved for building temples and palaces.

In the 1882 book Oahspe: A New Bible, John Newbrough included a map of a lost continent called "Pan" in the Northern Pacific, which some people connected to Mu. Newbrough said Pan disappeared 24,000 years ago and would rise again in the future.

Louis Jacolliot, a French lawyer and writer, wrote about a lost land called "Rutas" in ancient sources.

Criticism

Modern geological studies show that there are no large "lost continents" that have disappeared. According to the theory of plate tectonics, which scientists have confirmed since the 1970s, the Earth's crust is made of two types of rock. Lighter continental crust, called "sial" (rich in aluminum silicates), floats on heavier oceanic crust, called "sima" (rich in magnesium silicates). The sial is mostly found under continents, which are thick blocks of rock tens of kilometers deep. The ocean floor has much thinner crust, and sial is rarely found there. Because continents float on sima like icebergs float on water, they cannot sink into the ocean.

Continental drift and seafloor spreading can slowly change the shape and position of continents over millions of years. For example, the supercontinent Pangaea once broke apart. However, these changes happen extremely slowly, over hundreds of millions of years. Over the much shorter timespan of human history, the sima beneath continents is solid, and continents remain firmly in place. Scientists believe that continents and ocean floors have stayed in their current positions and shapes for the entire time humans have existed.

There is no evidence that continents have ever been destroyed. A continent’s massive sial rocks would need to disappear, but no such evidence exists at the bottom of the oceans. The islands in the Pacific Ocean are not parts of submerged landmasses but are instead the tops of isolated volcanoes.

This is true for Easter Island, which is a recent volcanic mountain surrounded by deep ocean (3,000 meters deep 30 kilometers away). In the 1930s, Alfred Métraux observed that the stone platforms where statues (moai) stand are located along the island’s current coastline, suggesting the island’s shape has not changed much since the statues were built. A path described by Pierre Loti that supposedly connected the island to underwater land is actually a natural lava flow. While Churchward was correct that Easter Island has no sandstone or sedimentary rocks, this detail is not important because the stone hats (pukao) on the statues are made of volcanic scoria, a type of rock found on the island.

Easter Island was first settled around 300 CE. The pukao on the moai are believed to have been ceremonial or traditional headdresses.