Is it in 800 AD or 1800 AD. Was it done in Rome? Was it done in India? What was the name of the surgeon?
Pre-19th century transplants are not well documented. The first possibly real human transplant was in India. It is unknown if it was successful or not:
The first reasonable account is of the Indian surgeon Sushruta in the 2nd century BC, who used autografted skin transplantation in nose reconstruction rhinoplasty. Success or failure of these procedures is not well documented. -Wikipedia
The first transplants known to be successful occurred in the 16th century:
Centuries later, the Italian surgeon Gasparo Tagliacozzi [1546 – 1599] performed successful skin autografts.
However, those were transplants from one part of the body to another in the same individual
The first between two individuals was in the 20th century:
In 1905, Eduard Zirm conducted the first successful transplant between two individuals. He transplanted the corneas of an 11-year-old boy into a Czech day laborer. That was the first successful human transplant between two individuals that has been verified.