What happened
In AD 105 Cai Lun presented his improved process to the court: tree bark, hemp waste, rags and old fishing nets pulped and dried into sheets. The Hou Hanshu, the official history of the Eastern Han, credits him as paper’s inventor.
Background
Archaeology has found earlier Western Han hemp paper from the 2nd century BC, so the accurate framing is that Cai Lun perfected and standardized the craft rather than inventing it alone. Paper gradually displaced bamboo strips and silk as writing materials.
Consequences
The craft spread along the Silk Road, reaching the Islamic world by the 8th century — tradition links the transfer to prisoners taken at the Battle of Talas in 751 — and Europe around the 12th century. Paper is counted among China’s Four Great Inventions, alongside printing, the compass and gunpowder.