The Highest Authority of the World Government

Above all the politic leaders within the World Government, be it kings of countries or mayors of cities there´s the Gorousei, which translated means Five Elder Stars. As the name indicates, it is a group of five older man, that lead the large government. Not much is known about their politic ideals, except for two things.

The one thing is that Great Pirate Age is a huge thorn in their eyes. The Gorousei consider it such a big problem that they even consider obtaining Ancient Weapons in order to stop the Pirate Age. This attitude can be considered radical since the Gorousei themselves fears these weapons because of their destructive power.

The other thing we know is that they made a law that forbids anyone to research on info on the blank 100 years of the worlds history. The motives of this are unclear but what is clear is that anybody who breaks this law gets the death penalty.

Besides that, there hasn't been much revealed about the Gorousei so far.

During the series we have seen many actions of the World Government. They don't seem to care about how the world is going into since they have only been seen caring about themselves. They worry about losing power and would do anything to protect their jobs.

Let's look at the certain points of the story:

20 Years ago, they ordered the burning of the island of Ohara for researching history. Nico Robin was the sole survivor, and due to her escape, she was given a very high bounty because of her ability to read Poneglyphs. They blame her for the possibility of reviving the ancient weapons when truthfully, Robin never cared about them. It was thought that the ancient weapon was what the WG was afraid of, but in reality they were afraid of the ancient kingdom and its ideals. Robin was hated by the world due to the WG.
12 years ago, a man name Spandam came before the Gorosei and convinced them to change their mind in preventing the revival of the ancient weapeon. They easily fell for his deceptions by ordering him to seize the blueprints.
Marine Captain Morgan brutely ruled Shelltown, and the Gorosei did nothing about it.
Orange Town was overridden by pirates, and the Gorosei did nothing about it.
Cocoyashi island was ruled by Arlong. He bribed a corrupted marine captain named Nezumi; the Gorosei did nothing about it.
There was a Coup de Etete in Villa, and the Gorosei did not care about it.
East Blue was mostly overrun by pirates, and the Gorosei did nothing about it. There weren't many marines patrolling the East Blue.
Drum was suffering because of its selfish king, and the Gorosei did nothing about it.
Arabasta was in war, and the Gorosei paid no attention to it until Smoker reported that Crocodile was behind it.
Spandam, the CP9 chief was planning to overthrow the World Government, and the Gorosei was unaware of this.