Drum Kingdom

The Drum Kingdom was a kingdom ruled by the royal family of Drum Island. It once had a kind ruler, and many of the greatest doctors on the Grand Line. But when the king died, and his son, Wapol came into power, things took a turn for the worse. Wapol issued that the 20 best doctors work excusively for him (the Isshi-20), while the rest of the doctors were banished or killed.

Then, the Blackbeard Pirates came and invaded the island, and Wapol fled in fear. Since then, Drum Island was left without a ruling government, and Dr. Kureha took residence in his castle. When Wapol came back to try to retake his kingdom, it was also the same time when the Straw Hat Pirates landed on the island, looking for a doctor to help a sick Nami. Luffy blow Wapol away from the kingdom, and since Wapol's defeat, it became the Sakura Kingdom, and is now ruled by Dalton.