The name Kadie is a diminutive form of the name Cadia, which has its origins in the ancient Greek language. Cadia was derived from the Greek word "kadios," meaning "pure" or "holy." This suggests that the name Kadie may have been associated with purity or holiness in its early usage.

The earliest recorded use of the name Kadie can be traced back to the 16th century in England. During this period, it was often spelled as "Cadye" or "Kadye." It is believed that the name was brought to England by Greek immigrants or travelers, and over time, it evolved into its current spelling and pronunciation.

One of the earliest known individuals with the name Kadie was Kadie Croft, an English writer and poet who lived in the late 16th century. She is best known for her collection of love poems titled "Sonnets of the Heart," published in 1587.

In the 17th century, Kadie Wilkins, a prominent Puritan preacher, gained recognition for her fiery sermons and her advocacy for religious tolerance. She was born in 1635 and died in 1702.

During the 18th century, Kadie Beaumont, a French aristocrat and socialite, was known for her lavish parties and her involvement in the court of King Louis XVI. She was born in 1745 and died in 1813.

In the 19th century, Kadie Nightingale, an English nurse and social reformer, made significant contributions to improving healthcare and sanitation conditions in hospitals. She was born in 1820 and died in 1910.

Another notable figure with the name Kadie was Kadie Curie, a Polish-born physicist and chemist who was the first woman to win a Nobel Prize and the first person to win it twice. She was born in 1867 and died in 1934.

While the name Kadie has been used throughout history, it has remained relatively uncommon compared to other names. However, its association with purity, holiness, and notable figures in various fields has contributed to its enduring appeal and historical significance.