The Sanlun school, also known as the Three Treatise school, was founded by Kumarajiva, a renowned Buddhist scholar and translator in China during the 4th century CE. Kumarajiva was born in the kingdom of Kucha, located in present-day Xinjiang, China. He was the son of a Brahmin scholar and was well-versed in Sanskrit, the language of Buddhist scriptures.

At a young age, Kumarajiva became interested in Buddhism and traveled to the ancient kingdom of Gandhara, located in present-day Afghanistan and Pakistan, to study under the guidance of renowned Buddhist masters. He spent several years there, mastering the teachings of the Madhyamaka school, particularly the works of Nagarjuna, the founder of the Madhyamaka philosophy.

After completing his studies, Kumarajiva returned to his homeland and began translating Buddhist texts from Sanskrit into Chinese. His translations were highly regarded for their accuracy and eloquence, and he soon gained a reputation as a great scholar and teacher. Many Chinese monks and scholars flocked to him to learn from his vast knowledge and wisdom.

Kumarajiva's teachings were based on the Madhyamaka philosophy, which emphasizes the concept of emptiness and the middle way between extremes. He also incorporated the teachings of Yogacara, another influential school of Mahayana Buddhism, into his teachings. Kumarajiva's teachings were a blend of both Madhyamaka and Yogacara, and this became the foundation of the Sanlun school.

The name Sanlun, which means "three treatises," refers to the three main texts that Kumarajiva translated and used as the basis for his teachings. These texts were the Madhyamakasastra (Treatise on the Middle Way), the Dvadashamukha (Twelve Gates), and the Shatadushani (One Hundred Verses). These texts were essential in expounding the Madhyamaka philosophy and were highly influential in the development of the Sanlun school.

Kumarajiva's teachings and translations had a significant impact on Chinese Buddhism, and the Sanlun school became one of the major schools of Chinese Buddhism, alongside the Tiantai and Huayan schools. His students continued to spread his teachings, and the Sanlun school flourished for several centuries, leaving a lasting impact on Chinese Buddhism.

In conclusion, Kumarajiva, a great Buddhist scholar and translator, founded the Sanlun school in China during the 4th century CE. His teachings, based on the Madhyamaka philosophy and the three treatises, had a profound influence on Chinese Buddhism and continue to be studied and practiced by many to this day.