The name Sydney has its origins in the Old English language, tracing back to the 9th century AD. It is derived from the Old English words "Sið" meaning "path" or "journey" and "ēg" meaning "island" or "dry ground." The combination of these words is thought to have formed the place name "Sið-ēg," referring to an area of dry ground along a path or route.

The name Sydney is believed to have first emerged as a surname, with one of the earliest recorded instances being in the Domesday Book of 1086, where it was listed as "Sydenye." This surname likely referred to someone who lived near a particular location called "Sið-ēg," which may have been a settlement or a landmark along a well-traveled path.

As a given name, Sydney gained popularity in the late Middle Ages, particularly in England. One of the earliest known individuals with the name Sydney was Sir William Sidney (c.1482-1554), a prominent English courtier and politician during the reigns of Henry VIII and Edward VI. Another notable figure was Sir Philip Sidney (1554-1586), an English poet, courtier, and soldier who was celebrated for his literary works, including the pastoral romance "Arcadia."

During the 16th and 17th centuries, the name Sydney became associated with nobility and aristocracy in England. Several members of the influential Sidney family held titles and positions of power, such as Robert Sidney, 1st Earl of Leicester (1563-1626), and Algernon Sidney (1623-1683), a prominent political theorist and opponent of absolute monarchy.

In the 18th century, Sydney Parkinson (1745-1771) was a notable Scottish botanical illustrator who accompanied Captain James Cook on his first voyage to the South Pacific. His detailed drawings and descriptions of the flora and fauna encountered during the expedition contributed significantly to the study of natural history.

Another famous bearer of the name was Sydney Smith (1771-1845), an English writer, philosopher, and Anglican cleric known for his wit and humor. He was a co-founder of the influential "Edinburgh Review" and a prominent social reformer of his time.

Throughout history, the name Sydney has been borne by various individuals from different walks of life, including writers, artists, politicians, and military figures. While its popularity has fluctuated over time, it remains a respected and well-recognized name with a rich historical legacy.