The Mokomo Dukedom is comprised of a sprawling city with several of its ancient buildings embedded in the surrounding rock formations and an area known as the Whale Forest that features a large whale-shaped tree. The entirety of the back is encircled by a large wall, with a gate located near Zunisha's tail.
At some point within the last 1000 years, the Mink Tribe established the Mokomo Dukedom on the back of Zunisha.
Seven days before the arrival of several of the Straw Hat Pirates, Jack and the Beasts Pirates invaded the Mokomo Dukedom in search of Raizo. The minks lied to the pirates that they had no knowledge of Raizo in order to keep him safe, and the two groups fought for five days. However, Jack won the battle by incapacitating the minks with Caesar's poisonous Koro gas, after which he and his men tortured them for information before leaving a day later to rescue Doflamingo. That day, Sanji's group reached Zou. Upon entering the forest, they ran into one of the Beasts Pirates, Sheepshead, who was chasing Tristan. They drove the Beasts Pirates away, cleared the gas, and saved the lives of all the minks. The dukedom suffered heavy damage during these events, and the minks have not yet rebuilt and returned to their homes.