They are the largest of the upland ethnic groups of the Central Highlands known as Degar or Montagnards and they make up 23% of the population of Ratanakiri Province in Cambodia.

[6] Studies about the Jarai people and their culture have mainly focused on their language and were made by evangelical groups seeking conversions.

The first reports come from the French colony during the 19th century that demarcated the border between Vietnam and Cambodia, dividing the Jarai territory and letting a small portion in what is today Ratanakiri Province.

In a DNA test to some Jarai students in Cambodia in 2017, they presented evidences of belonging to the Haplogroup T-M184[8] that originates more than 25 thousand years ago at the Mediterranean Basin.

[9][10] Archaeological sites from the culture have been discovered from the Mekong Delta to Quang Binh province in central Vietnam.

[12] The kingdom was known variously as nagara Campa (Sanskrit: नगरः कम्पः; Khmer: ចាម្ប៉ា) in the Chamic and Cambodian inscriptions, Chăm Pa in Vietnamese (Chiêm Thành in Sino-Vietnamese vocabulary) and 占城 (Zhànchéng) in Chinese records.

The destruction of Champa caused the spread of different tribes in the regions of what is today Vietnam, Laos and Cambodia sharing the same linguistic root like the Jarai People.

Trades between highlanders and lowlanders living around the Gulf of Thailand happened around the 4th century A.C.,[13] but there were also raids led by Khmer, Lao and Thai slave traders.

The region was incorporated to the French Indochina colony in 1893 and the slave trade was abolished,[15] but indigenous peoples were used for the huge rubber plantations.

Bouillevaux, a French missionary that made an incursion through the Mekong in 1850 and mentioned about certain "King of Fire", a man of respect belonging to a certain group of people called Jarai.

[19] At the same time, US Evangelists entered in contact with Jarai people and published Bibles in their language (excluding the Khmer Jarai-Ede).

The Jarai-Ede Bibles created some literacy to them, but after the Vietnamese reunification in 1975, most of the Jarai assistants of the US military, were evacuated from their land to United States.

The goal of the Montagnard Degar was to create an independent state in the Vietnamese highlands, consisting entirely of indigenous people groups.

In Vietnam, some Jarai persons seek for refuge in other countries, crossing the Cambodian territory to escape restrictions of their traditions and cultures.

A recurrent element has to see with the stories about three kings: Fire, Water and Wind and a Sacred Sword that came down from heaven to give to the Dega Jarai people great powers.

The Jarai kings attract even persons from other ethnic groups that believe in their influences over the mysteries of the human nature and the souls of all living things.

In contrast to terse political and religious pressure in Vietnam, Buddhism and Jarai animism have a rather peaceful and harmonious relationship with each other.

Islam began to be recorded as having been spread to the Jarai people in the highlands during the Katip Sumat uprising in 1833 to early 1834.

Upon his return from Kelantan, he spread Islam[who] to the Churu and Jarai peoples and recruited them to participate in the Jihad movement against Đại Việt.

The Jarai nights in the villages or inside the house clan are animated by their ancestral music performs with gongs, xylophones such as t'rưng, zithers, mouth fiddle k'ni, and various other traditional instruments, many of them made of wood and bamboo.

The music and dance are monotonous and nostalgic, creating a close relation with the jungle, the natural environment of the people.

In 1996 Dock Rmah, a prominent Jarai musician living in the United States, received a Folk Heritage Award from the North Carolina Arts Council.