---
node: first_opium_war
type: event
slug: first_opium_war
title: "First Opium War"
lead: "Britain and Qing China fought from 1839 to 1842 after the Qing cracked down on the illegal British opium trade. The Treaty of Nanking that ended it was the first of the 'unequal treaties'."
published: 2026-07-09
updated: 2026-07-09
image_file: first_opium_war.jpg
image_source: "https://commons.wikimedia.org/wiki/File:Destroying_Chinese_war_junks,_by_E._Duncan_(1843).jpg"
image_author: "Edward Duncan"
image_license: "Public domain"
---

## What happened

War broke out between Britain and Qing China in 1839 and lasted until 1842. British naval and artillery superiority decided the fighting.

## Background

The trigger was the Qing crackdown on the illegal British opium trade: in 1839 commissioner Lin Zexu confiscated and destroyed about 20,000 chests of opium at Humen.

## Consequences

The Treaty of Nanking (August 1842) ceded Hong Kong Island to Britain, opened five ports — Guangzhou, Xiamen, Fuzhou, Ningbo, and Shanghai — to British trade, and imposed an indemnity; supplementary treaties added extraterritoriality. It was the first of the "unequal treaties", the start of what Chinese historiography calls the century of humiliation, and the opening wedge for foreign privileges in China.