The Origin of Som Tum Papaya Salad May Surprise You

Go anywhere in Thailand or any Thai restaurant around the world and you will encounter som tum, the ubiquitous green papaya salad. Many of us assume som tum (or som tam) is a Thai dish - in the world's eyes som tum is as quintessentially Thai as tom yam and pad Thai.

Today, som tam is synonymous with Thai cuisine and it is popular throughout Thailand (from gritty street pavements to glitzy Michelin starred restaurants) and around the world as a Thai dish.

CNN lists som tam as one of "The World's 50 Best Foods" and attributed it to Thailand.

But, the origin of som tum may surprise you.

Before we go any further - What is som tum?

Som tum is a salad of shredded slivers of crunchy sour green papaya tossed with hot chili pepper, raw garlic, green long bean, cherry tomato, dried krill (or small shrimp), carrot, roasted peanut tossed in tangy lime juice and umami savoury fish sauce.

It's a riot of sharply sour, spicy, sweet, savoury-salty, tannic and nutty flavours which is often often paired with sweet sticky rice. But, som tam is an appetising versatile dish that goes well with many dishes such as greasy larb, smokey grills and deep fried crisps. So yeah, whenever you eat Thai, a side of som tam is almost inevitable.

Som tam recipes vary from region to region, even stall to stall - some add palm sugar, green eggplant, even pickled small crab, but the definitive ingredient is green papaya. There will always be green papaya in classic som tam. Some stalls pound and mash their green papaya, while other stalls keep them snappy and crisp. But, if there is no green papaya, it is not classic som tum.

Som tam has its roots in Thailand's eastern neighbour Laos.

In Laos (and also in the Isaan region of Thailand), green papaya salad is known as tum bak hoong (also tam mak hoong) - tum / tam means "to pound" and bak hoong means "papaya" i.e. "pounded papaya". The Lao version has young eggplant and uses fermented fish paste instead of fish sauce.

In Thailand (beyond Isaan), tum bak hoong becomes som tum - som means "sour" so the salad became "pounded sour".

(Etymologically "pounded sour" could mean anything sour and not necessarily green papaya. So, "som tam" can be made without green papaya. There's "som tam" made with green mango, wing bean, cucumber, guava, even sweet corn, etc as the main ingredient. There's also a theory that the dish was originally known as som tam which can be any "sour" but is now synonymous with green papaya salad because it is the most popular "sour".)

History of Som Tam is the History of Laos & Thailand

To appreciate the link between Isaan, Laos and som tam, we need to go a little further back in history.

The history of som tam is the history of the ebb and flow, rise and fall of kingdoms and empires in mainland Southeast Asia.

Mainland Southeast Asia 13th Century (left), 1900s after the Franco-Siamese War (right)

At the end of the 13th century, the area which is Laos today was largely unoccupied. The dominant empires at that time were Angkor (Khmer / Cambodian), Sukhothai, Lan Na, Dai Viet, and Champa.

(To put it in context, the kingdom of Singapura was founded in 1299 i.e. around the same time.)

In 1540, the area which is Laos today was part of the empires of Cambodia and Lan Xang.

Papaya is not a native plant of Southeast Asia. The Spaniards and Portuguese brought it here from their colonies in central America in the 1550s, first to the Philippines and then to mainland Southeast Asia.

Mainland Southeast Asia before (left) and after the Franco - Siamese war of 1893 (right)

In the 18th century, the mighty Lan Xang kingdom broke up into the Lao kingdoms of Luang Prabang, Vientiane, and Champasak.

Between 1779 and 1893, Vientiane and Champasak were absorbed by Siam while Luang Prabang became Siam's vassal state i.e. Laotians lost all their kingdoms.

Laos was "re-created" by the French after defeating the Thais in the Franco - Siamese war of 1893. The Mekong River became the boundary between Laos and Thailand. By this division, parts of the former kingdoms of Luang Prabang, Vientiane and Champasak remained as part of Thailand, namely the Isaan region.

Today, 16 million ethnic Lao people live in Thailand (mostly in Isaan) while 5 million live in Laos. This accounts for why there are similarities between Thai, Isaan and Lao cuisine. Examples include som tam / tam maak hoong and sticky rice.

In the classical 1908 Thai cookbook “A Gourmet Cook’s Recipes” by Lady Plian Phasakonwong, there was no mention of som tam or tam mak hoong. This could mean that at that time, som tam was not yet as popular among Thais as it is today.

Things changed when people from Isaan migrated all over Thailand, especially to Bangkok the capital, for work. The peak was during the economic boom of the 1980s. Migrant workers from Isaan brought tam mak hoong with them. The appetising salad became popular and from their firm base in Thailand, spring-boarded around the world as a Thai cultural icon. So the rise of som tam in Thai cuisine was a fairly recent phenomenon though no one is certain exactly when it happened.