The name Ian is derived from the Hebrew name Yochanan, meaning "Yahweh is gracious." This name is the origin of the English name John, with Ian being a Scottish Gaelic derivative. The name first emerged in Scotland during the Middle Ages.

One of the earliest recorded uses of the name Ian can be found in the early 13th century Scottish text "The Brus," which chronicles the life of Robert the Bruce, King of Scots from 1306 to 1329. The text mentions "Ian de Bretayn," referring to a knight who fought alongside Robert the Bruce.

In the 16th century, the name Ian gained popularity among Scottish nobility. One notable bearer of the name was Sir Ian Moncreiffe of that Ilk, a Scottish baronet who lived from 1537 to 1594. He served as a diplomat and was known for his role in the Reformation in Scotland.

Another historical figure with the name Ian was Ian Lom MacDonald, a Scottish poet and warrior who lived from around 1624 to 1709. He was a member of the Clan Donald and is renowned for his eloquent Gaelic poetry, which documented the turbulent events of his time.

In the 18th century, Ian Douglas, 14th Earl of Morton (1701-1768), was a prominent Scottish nobleman and politician. He served as the Lord President of the Court of Session, the highest civil court in Scotland, from 1757 to 1766.

During the 19th century, Sir Ian Hamilton (1853-1947) was a British Army officer who rose to the rank of General and served in various campaigns, including the Second Boer War and World War I. He is remembered for his role in the Gallipoli Campaign in 1915.

Over time, the name Ian has become popular not only in Scotland but also in other parts of the English-speaking world, often chosen for its Scottish heritage and strong, masculine sound.