Tatiana (or Tatianna, also romanized as Tatyana, Tatjana, Tatijana, etc.) is a female name of Sabine-Roman origin that became widespread in Eastern Europe. Origin. Tatiana is a feminine, diminutive derivative of the Sabine—and later Latin—name Tatius. King Titus Tatius was the name of a legendary ruler of the Sabines, an Italic tribe living near Rome around the 8th century BC. After the Romans absorbed the Sabines, the name Tatius remained in use in the Roman world, into the first centuries of Christianity, as well as the masculine diminutive Tatianus and its feminine counterpart, Tatiana.
https://en.wikipedia.org/wiki/Tatiana