The name Knox has its origins in the medieval Scottish surname Knox, which is an Anglicized version of the Gaelic name "Cnoc" meaning "hill" or "hillock". It is believed to have originated as a descriptive name for someone who lived near a hill or on high ground.

The earliest recorded use of the name Knox as a given name dates back to the 16th century, when it gained prominence due to the Scottish Protestant reformer John Knox (1514-1572). He played a pivotal role in the Scottish Reformation and is regarded as the founder of the Presbyterian Church in Scotland.

Another notable bearer of the name Knox was Henry Knox (1750-1806), an American bookseller who became the chief artillery officer of the Continental Army during the American Revolutionary War. He was instrumental in the success of the Patriot forces, particularly at the Siege of Boston and the Battle of Yorktown.

In literature, the name Knox appears in the works of acclaimed Scottish author Sir Walter Scott (1771-1832), who featured characters bearing the name in his historical novels, such as "The Abbot" and "The Monastery".

Philander Chase Knox (1853-1921) was an American lawyer and politician who served as the 36th United States Secretary of State under President William Howard Taft from 1909 to 1913.

Another notable figure was Frank Knox (1874-1944), an American newspaper editor and publisher who served as the United States Secretary of the Navy during World War II under President Franklin D. Roosevelt.

While the name Knox has its roots in Scotland, it has been adopted and used worldwide, particularly in English-speaking countries. Its association with historical figures and its strong Scottish heritage have contributed to its enduring popularity as a given name over the centuries.