Agrihan Island

Northern Mariana Islands



Roberton was a mercenary and a pirate. He was a Scotsman who, in 1817, was in the employ of the Chileans fighting against the Spanish. He was of medium height, red hair and “a repugnant sight” and was known to be savage and cruel.


A couple of years later, he was involved in the attempt to capture the bandit Benavides. He captured a friend of the bandit, a man named Pacheco, in Arauco, Chile. He “extracted” information as to the whereabouts of Benavides from Pacheco. With a small army, he took Benavides by surprise and captured his men. Benavides escaped. Roberton hanged all sixty men in a clearing, but not before getting information from them. They told of booty hidden on the island of Mocha, off the coast of Chile. Roberton moved there with his brother and some others loyal to him. One day, while in a small boat on their way back from Valdivia, his brother and most of his men drowned. Roberton could not continue his existence there and left to join the Peruvian Navy. There is no further mention of the loot buried on Mocha.


While in the employ of Peru, he fought at the siege of Lima, was captured and released. He rejoined the Peruvian Navy and was living in Lima when he met Teresa Mendez.


Teresa was a 21-year-old widow of a Spanish sea captain. She was not only wealthy, but renown for her beauty. She had many suitors, but would only show interest in those of wealth and noble birth. Roberton was neither of these, but he was enamored. He pursued her to no avail. When he declared his love, she laughed at him. He persisted and she told him that if he could provide her with great wealth, she would promise herself to him. Everyone knew this would not happen.


Anchored in the harbor was the English ship Peruana. While at a meeting of naval officers, Lieutenant Vieyra joked that if Roberton could take the Peruana, he would have the money to show Teresa he was a man of means. The ship had 2 million gold piastres on board.


That night, Roberton rounded up a gang of sailors, mostly British. They attacked the poorly guarded Peruana that night and left the harbor with the ship and it’s treasure. By morning the ship, Roberton and his men were long gone.


They sailed to Tahiti. Roberton knew they had a head start on their pursuers, but he also knew they would be pursued.  He needed to convince his men to leave Tahiti and was met with some reluctance. His two most trusted men were a couple of Irishmen named George and William. Using a combination of threats and the lure of 15 Tahitian women they loaded on board, Roberton was able to get the crew to set sail again.


Roberton’s intent all along was to have this treasure for Teresa and him. Sharing it with 15 men and the Tahitian women was not part of the plan. He sailed northwest toward the Mariana Islands. At one anchorage, where he put in to load on water, he declared that 8 of his men were plotting to take over and marooned them on the deserted island.  He sailed on to the Island of Agrihan.



The first task was to slaughter the women. William was an expert marksman and started shooting the women. Some made it overboard and were swimming to the island, but William did not miss often. None of Tahitian women survived.


Next, the 7 remaining crewmembers loaded the chests containing the gold coins onto a boat and rowed to shore. They prepared a clearing at the foot of a cliff a short distance from the sea. They then buried the chests. They chopped down some trees and left some markings on the rocks to identify the area. They then set sail for Hawaii.


As they neared the Hawaiian Islands, Roberton put the next phase of his plan in place. He, George and William sealed the rest of the men in the hold of the ship. They had kept 20,000 gold pieces for their own use, climbed into a life raft and scuttled the ship. They rowed to Oahu and told of a shipwreck and how they were the only survivors.


The plan would have worked and no one would have ever found out about the marooned men, the Tahitian women, the gold being buried and the scuttling of his ship except for one thing. They did a bad job on the scuttling. The ship remained afloat. A couple of weeks after Roberton landed in Oahu, a whaling ship came across the drifting vessel. Three of the men had starved to death and one still clung to life. It took a year before the ship made it back to harbor. It landed in Oahu. Roberton and the Irishmen were already gone. The lone survivor retold his story to Gabriel Lafond de Lurcy who wrote the tale in “Voyages Autour du Monde”.




Situated 206 nautical miles north of Saipan with an
area of 11.4 square miles.  This volcano has gentle
slopes near the shore on the southeast and southwest
sides with the crater entrance on the north side.
The remaining island consists of steep slopes and deep
gorges.  The coast is rocky and steep with a landing beach
only on the southwest coast.
Highest point 3,166 ft.



The three were hunted men. They traveled to Brazil. George disappeared in Rio de Janeiro; we can only guess what happened. William and Roberton stayed together constantly, probably with a great deal of distrust between them.  They needed the treasure money so they began to make their way back to Agrihan. They arrived in Hobart, Tasmania and convinced an old sailor named Thomson to gather a small crew and take them north.


Thomson got William drunk one night and William told the whole story. William did not know the name of the island where the treasure was buried, but his description convinced Thomson that it must be Agrihan. Thomson awoke one night to the sounds of screams. William had been murdered. Thomson was now very worried about Roberton. He kept watch, but was no match for the younger stronger man. One day, Roberton just threw Thomson overboard.


But Thomson was very lucky. He managed to keep afloat for some time. A Spanish ship found him, almost dead, and he told them his story. The Spanish pursued Roberton. When Roberton reach Saipan, he jumped ship. He went into the mountains to hide, but to no avail. The Spanish captured him.


The Spanish took Roberton to Agrihan. He would tell them nothing. They forced him onto the island to show them the location, but he just stalled, looking for chances to escape. They took him back onto the ship and using the whip, convinced him to cooperate. Roberton must have known his position was hopeless. If he refused to show them the treasure location, he would be tortured. If he showed them the location, he would be killed and the Spanish would get the gold. He was not going to allow the men that captured and tortured him to profit. While the Spanish were taking him back to the island, he jumped overboard. His chains took him quickly to the bottom of the sea. He never did see Teresa after that night he decided to take the treasure.





The Spanish governor of the Marianas hired 600 natives to search for the treasure. They came up empty handed. Some believe that the inlet on the southern most west side of the island is the most likely burial site for the treasure.