(–1307 BC) in the United States (1946), direct antecedents of modern-day flip-flops. Thong sandals have been worn for thousands of years, as shown in images of them in
ancient Egyptian murals from 4,000 BC. A pair found in
Europe was made of
papyrus leaves and
dated to be approximately 1,500 years old. These early versions of flip-flops were made from a wide variety of materials. Ancient Egyptian sandals were made from papyrus and palm leaves. The
Maasai people of
Africa made them out of
rawhide. In
India, they were made from
wood. In
China and
Japan,
rice straw was used. The leaves of the
sisal plant were used to make
twine for sandals in
South America, while the natives of
Mexico used the
yucca plant. The
ancient Greeks and
Romans wore versions of flip-flops as well. In Greek sandals, the toe strap was worn between the first and second toes, while Roman sandals had the strap between the second and third toes. These differ from the sandals worn by the
Mesopotamians, with the strap between the third and fourth toes. In
India, a related "toe knob" sandal was common, with no straps but instead a small knob located between the first and second toes. They are known as
Padukas. The modern flip-flop became popular in the
United States as soldiers returning from
World War II brought Japanese
zōri with them. It caught on in the 1950s during the
postwar boom and after the end of hostilities of the
Korean War. As they became adopted into American popular culture, the sandals were redesigned and made in the bright colors that dominated 1950s design. They quickly became popular due to their convenience and comfort, and were popular in beach-themed stores and as summer shoes. During the 1960s, flip-flops became firmly associated with the beach lifestyle of
California. As such, they were promoted as primarily a
casual accessory, typically worn with
shorts,
bathing suits, or summer dresses. When they became more popular, some people started wearing them for dressier or more formal occasions. By 2019, production tops 200 million pairs per year. Prices range from under $5 for basics to more than $50 for high-end fashion models. Flip-flops quickly became popular as casual footwear for young adults. Girls would often decorate their flip-flops with metallic finishes, charms, chains, beads,
rhinestones, or other jewelry. Modern flip-flops are available in leather, suede, cloth or synthetic materials such as plastic. Platform and high-heeled variants of the sandals began to appear in the 1990s, and in the late 2010s,
kitten heeled "kit-flops". In the U.S., flip-flops with college colors and logos became common for fans to wear to intercollegiate games. In 2011, while vacationing in his native
Hawaii,
Barack Obama became the first President of the United States to be photographed wearing a pair of flip-flops. The
Dalai Lama of
Tibet is also a frequent wearer of flip-flops and has met with several U.S. presidents, including
George W. Bush and
Barack Obama, while wearing the sandals. While exact sales figures for flip-flops are difficult to obtain due to the large number of stores and manufacturers involved, the Atlanta-based company Flip Flop Shops claimed that the shoes were responsible for a $20 billion industry in 2009. Furthermore, sales of flip-flops exceeded those of
sneakers for the first time in 2006. If these figures are accurate, it is remarkable considering the low cost of most flip-flops. ==Design and custom==