The name Kati is a diminutive form of the feminine name Katarina, which is derived from the Greek name Aikaterine. This name ultimately traces its roots back to the Greek word "katharos," meaning "pure." The name Kati emerged as a shortened version, likely used as a nickname or informal variant.

Kati was particularly popular in various Slavic cultures, including those of Russia, Poland, and the Balkans. The name's origin can be traced back to the Byzantine Empire and the Eastern Orthodox Christian tradition, where it held significance as a name associated with purity and virtue.

Historically, the name Kati appeared in various medieval records and documents, though its earliest recorded use is difficult to pinpoint due to variations in spelling and regional adaptations. One notable early reference is found in the 12th-century Russian epic poem "The Tale of Igor's Campaign," where a character named Katerina is mentioned.

Throughout history, several notable individuals have borne the name Kati, including:

1. Kati of Racconigi (c. 1492-1578), an Italian noblewoman and regent of Montferrat.
2. Kati Popova (1829-1893), a Bulgarian educator and feminist activist known for her efforts in promoting women's education.
3. Kati Marton (born 1949), a Hungarian-American author and journalist, known for her biographies of various political figures.
4. Kati Wolf (born 1953), a Hungarian-American actress known for her roles in films like "The Unbearable Lightness of Being" and "The Princess Bride."
5. Kati Terlizzi (born 1963), an Italian actress and television presenter, known for her work in Italian cinema and television.

While the name Kati has its roots in ancient Greek and Byzantine traditions, it has been embraced and adapted by various cultures throughout history, reflecting its enduring appeal and versatility across different regions and eras.