Vietnamese Thiền, also known as Vietnamese Zen Buddhism, has a rich and complex history that dates back to the 6th century. Its roots can be traced to the teachings of the Indian monk Bodhidharma, who is considered the founder of Zen Buddhism.

In the 6th century, Bodhidharma traveled to China and introduced the practice of meditation to the Chinese people. This form of meditation, known as Chan in Chinese, became the basis for the development of Zen Buddhism. Over time, Chan Buddhism spread to other East Asian countries, including Vietnam.

The first record of Zen Buddhism in Vietnam can be found in the 7th century, during the reign of the Tang Dynasty in China. This was a time of cultural exchange between China and Vietnam, and many Chinese monks traveled to Vietnam to spread the teachings of Chan Buddhism. One of these monks, Vinitaruci, is credited with establishing the first Zen monastery in Vietnam.

However, it was not until the 13th century that Zen Buddhism truly took hold in Vietnam. This was due to the efforts of the Vietnamese monk, Thích Thông Triệt, who traveled to China to study under the famous Zen master, Linji Yixuan. Upon his return to Vietnam, Thích Thông Triệt established the first Vietnamese Zen school, known as the Lâm Tế (Linji) school.

Under Thích Thông Triệt's leadership, the Lâm Tế school became the dominant form of Buddhism in Vietnam. It emphasized the practice of meditation and the attainment of enlightenment through direct experience, rather than through scripture or ritual.

In the 15th century, a new Zen school emerged in Vietnam, known as the Trúc Lâm (Bamboo Forest) school. This school was founded by the Vietnamese emperor Trần Nhân Tông, who had studied under a Chinese Zen master. The Trúc Lâm school emphasized the integration of Zen practice with Confucianism and Taoism, making it more accessible to the general population.

During the 17th and 18th centuries, Zen Buddhism faced persecution and decline in Vietnam due to political and social upheavals. However, it experienced a revival in the 19th century, with the establishment of the Tự Đức (Self-Realization) school by the Vietnamese monk, Huệ Nghiêm. This school combined elements of both the Lâm Tế and Trúc Lâm schools and became the most widely practiced form of Zen in Vietnam.

Today, Vietnamese Thiền continues to thrive in Vietnam and has also spread to other countries, such as the United States and France. It has evolved and adapted to modern times, but its core teachings of meditation, mindfulness, and enlightenment remain unchanged. Vietnamese Thiền is a testament to the enduring legacy of Bodhidharma and the resilience of Zen Buddhism.