The only surviving Roman palace of the first order was built by Emperor Diocletian.
Explanation:
1. Diocletian was a Roman emperor who ruled from 284 to 305 AD.
2. He built his palace in Split, Croatia, which is known as Diocletian's Palace.
3. This palace is considered the only surviving Roman palace of the first order, characterized by its grandeur and significance.
4. The palace served as a residence for Diocletian during his retirement and also had administrative functions.
5. Today, Diocletian's Palace is a UNESCO World Heritage site and a popular tourist attraction, showcasing the architectural and historical richness of the Roman era.
