Khmer Deity Head, Asura Head
Sandstone figures line the entryways and walkways of Cambodia's ancient temples, and looters have hacked off ancient heads and limbs. This stone head of a male deity dates back to the 9th Century, and this head of a demon, or asura, dates back to the 12th Century. UNESCO says private collectors purchased these objects from reputable dealers, and the collectors donated the pieces to the Honolulu Academy of Arts in the early 1990s.
Now: The pieces were identified as artifacts looted from the Angkor complex. The Honolulu Academy of Arts returned the heads to Phnom Penh in 2002.
Euphronios Krater
This vessel was used in ancient times to mix water and wine. New York's Metropolitan Museum of Art purchased the piece in 1972 for $1 million.
Originated: It is of Greek origin and dates back to around 515 B.C.
Now: Italy pressed for the krater's return, saying it was likely looted from a tomb near Rome. The Met agreed in 2006 to return the Euphronios krater and other artifacts to Italy in exchange for long-term loans from Italy.
Inca Artifacts
Nearly a century ago, American archaeologist Hiram Bingham explored the then-largely unknown Inca city of Machu Picchu in Peru.
Originated: Machu Picchu
Displayed: Objects and fragments uncovered during the 1912 expedition are now at the Peabody Museum at Yale University, in the northeastern U.S. state of Connecticut. The collection is made up of ceramic, metal and stone fragments and objects, as well as pieces of animal and human bone. Yale says about 300 of the more than 5,000 items are museum-quality.
Now: Peru has filed legal challenges through the U.S. court system, and it has also dropped some legal claims, as well. Yale says it was obligated to return some items to Peru and it did so in the 1920s. Yale says it has no further legal obligation to return artifacts that remain in the Peabody Museum, which it says are used for research and educational purposes.
Benin Bronze
Some of these elaborate bronze plaques are believed to have adorned the king's (oba's) palace in Benin City. In 1897, British forces forces seized hundreds of bronze artifacts from the kingdom of Benin, present-day Nigeria, during the British Punitive Expedition.
Originated: Kingdom of Benin, 16th Century
Displayed: The British Museum
Now: The Nigerian government has pressed for the return of bronze plaques that remain in the British Museum's collection.
Rosetta Stone
The Rosetta Stone features the same inscription in three languages -- Greek, an Egyptian script called Demotic and Egyptian hieroglyphics. Scholars used the two known languages, Greek and Demotic, to decipher hieroglyphics.
Originated: Egypt, 196 B.C.
Displayed: British Museum since 1802, with the exception of a period during WWI when it was placed elsewhere for safekeeping.Napoleon's Army uncovered the stone while digging near a fort in Rashid (Rosetta) in 1799. After the British military defeated Napoleon's forces in Egypt, various antiquities including the Rosetta Stone were ceded to Britain in 1801.
Now: One of the six pieces Egypt's antiquities chief Zahi Hawass has on Egypt's so-called "wish list" of most wanted artifacts.
Parthenon Sculptures (also known as the Elgin Marbles)
The Parthenon was built as a tribute to the Greek goddess Athena, and the sides of the massive white marble temple were adorned with decorative carvings. Over the centuries, the once glorious temple fell into a state of ruin. In the early 1800s, the Ottoman authorities that ruled Athens granted Britain's Ambassador to the Ottoman Empire, Thomas Bruce, the Earl of Elgin, permission to remove half of the remaining sculptures from the temple.
Originated: Athens, Greece, 432 B.C.
Displayed: British Museum since 1817
Now: Greece is campaigning for the return of the sculptures so they can be displayed with other other sculptures from the Parthenon at the Acropolis Museum in Athens. The British Museum says it legally obtained the sculptures, and it says it is educational for people to see these ancient Greek works in the context of an international museum.
Bust of Nefertiti
Queen Nefertiti, known for her legendary beauty, was the wife of Pharaoh Akhenaten some 3,400 years ago. German archaeologist Ludwig Borchardt uncovered this bust during an excavation in Egypt in 1912. At the time, Germany and Egypt agreed to divvy up the artifacts that were unearthed, and the bust was sent to Germany.
Originated: Egypt, around 1340 B.C.
Displayed: The Bust of Nefertiti went on display in Germany in 1923. It has been at Berlin's Neues Museum since 2009.
Now: One of the six pieces Egypt's antiquities chief Zahi Hawass has on Egypt's so-called "wish list" of most wanted artifacts. Hawass has raised questions about whether the bust was taken out of Egypt under false pretenses, but Germany says it was fairly acquired.
Image: creative commons
Royal Manuscripts of the Joseon Dynasty
A collection of South Korean royal books details royal ceremonies and court life of the Joseon Dynasty. France invaded Ganghwa island off the coast of Korea in 1866, and French troops seized manuscripts from the Oegyujanggak royal library.
Originated: South Korea, during the Joseon Dynasty (1392-1910)
Displayed: Nearly 300 manuscripts are held in the French National Library in Paris.
Now: South Korea's Foreign Minister Yu Myung-hwan and his French counterpart Bernard Kouchner discussed this collection when they met in March 2010. Minister Yu repeated his government's request to have the manuscripts returned. In 1993, Paris returned one of the volumes in its possession to South Korea.