Cai Lun: A Detailed Biography

Cai Lun (c. 50–121 CE) was the Chinese eunuch official traditionally credited with inventing modern papermaking in 105 CE — one of the Four Great Inventions of ancient China. His affordable paper replaced expensive silk and bamboo, revolutionising writing, record-keeping, and the spread of knowledge across the world. This biography covers his rise in the Han court, papermaking breakthrough, political downfall, and enduring legacy, as documented by the Encyclopaedia Britannica, the Silk Road Foundation, and the China Highlights.

Early Life and Palace Career

Eunuch in the Han Court

Born around 50–60 CE in Guiyang commandery (modern Leiyang, Hunan), Cai Lun was castrated young to enter imperial service. By the 70s CE he served in the palace of Emperor Zhang, rising through ranks due to intelligence and loyalty, as detailed by the Metropolitan Museum of Art.

Invention of Paper (105 CE)

Appointed director of imperial workshops under Emperor He, Cai Lun improved papermaking using mulberry bark, hemp, old rags, and fish nets. He presented his lightweight, durable paper to the emperor in 105 CE. The court adopted it rapidly, replacing bamboo strips and silk, as recorded in the Hou Hanshu (Book of the Later Han), preserved by the Chinese Text Project.

Spread of Papermaking

Cai Lun’s method spread across China by the 3rd century, reached Korea and Japan by the 7th, the Islamic world via Samarkand in the 8th (Battle of Talas 751), and Europe by the 12th century — transforming literacy worldwide, as documented by the Silk Road Foundation.

Political Power and Downfall

Cai Lun became one of Emperor He’s most trusted advisors and was ennobled as marquis. After Emperor He’s death in 105 CE and Empress Deng’s regency, he was implicated in palace intrigues (possibly the death of Empress Deng’s rival). Facing arrest, he bathed, dressed in fine robes, and drank poison in 121 CE, as recorded by the China Knowledge.

Personal Life

As a eunuch, Cai Lun had no children. He was known for refined manners and devotion to duty. His invention earned him posthumous honours — temples were built to him as the god of papermaking.

Death and Legacy

Cai Lun’s Enduring Impact

Cai Lun died by suicide in 121 CE. Deified as the patron of papermakers, his statue stands in Chinese paper museums. The year 105 CE is considered the birth of modern paper. Without Cai Lun’s affordable medium, the spread of Buddhism, Islam, and the Renaissance would have been far slower. UNESCO included Chinese papermaking on its Intangible Cultural Heritage list in 2009, as celebrated by the UNESCO.

Frequently Asked Questions About Cai Lun

Why Is Cai Lun Famous?

For inventing modern papermaking in 105 CE.

Did Cai Lun Really Invent Paper?

He perfected the process — crude paper existed earlier.

Where Was Cai Lun Born?

Guiyang (Hunan), c. 50–60 CE.

Was Cai Lun a Eunuch?

Yes — castrated to serve in the palace.

What Materials Did Cai Lun Use?

Mulberry bark, hemp, rags, fish nets.

Why Was Cai Lun Executed?

Forced suicide in 121 CE after palace intrigue.

How Did Cai Lun Die?

Drank poison in 121 CE.