Given how many pirates there are, it is a puzzling matter as to how the Marines of One Piece are able to push them back. Numerous more pirates appeared all over the place following the death of Gold Roger and the start of the Great Pirate Era.
The Four Emperors of the New World were only just starting to establish their dominance and realms. The Marines had to adapt to the changing reality if they were to keep their position of authority. The Seven Warlords of the Sea came into being in this manner.
What Is the Point of One Piece's Seven Sea Warlords?
The Seven Warlords of the Sea was a system created by the World Government in response to the growing number of pirates. Seven different pirate crews would have their crimes pardoned and their bounties nullified. They were free to go about their goals, as long as this doesn't directly interfere with Marine Headquarters or World Government interests.
Warlords are expected to perform any tasks assigned to them, such as when Bartholomew Kuma was ordered to kill the Straw Hat Pirates on Thriller Bark, as well as obey summons by the Government in times of crisis, such as the execution of Portgaz D. Ace. This principle has gotten those who take the title of Warlord the moniker of "Government Dogs" by other pirates, as they throw away their pride as a swashbuckler in favor of government protection.
The Seven Warloads of the Sea in Pieces: Who Are They?
When Dracula Mihawk destroyed Don Krieg's ship and subsequently engaged in combat with Zoro in Chapter 50, the first Warlord, Dracula Mihawk, was first presented. However, Yosaku's casual reference of Jimbei in chapter 69—a figure who doesn't truly debut until Impel Down—left readers without a comprehensive explanation of the Seven Warlords concept. The idea of Warlord is really partly inspired on genuine privateers. Old European countries deployed privateers, who were authorized pirates, to rob ships, assault colonies, and engage in other piracy.
There are 11 known characters in One Piece who have held the title of Warlord at one point or another. However, the seven most recognizable Warlords are as follows: Dracula "Hawk-Eye" Mihawk, "The Tyrant" Bartholomew Kuma, Boa Hancock the Pirate Empress, Sir Crocodile, Gecko Moria, "First Son of the Sea" Jimbei and "Heavenly Yaksha" Donquiotxte Doflamingo. A few other characters would later hold the title of Warlord for a period of time, including "Surgeon of Death" Trafalgar Law, Buggy the Clown, Marshall D. Teach and Edward Weevil.
Interestingly, each Warlord has a specific reason for taking the title, noble or otherwise. For instance, Boa Hancock uses her title of Warlord to maintain her home, Amazon Lily, as a closed-off nation where the World Government or Marines can't impose their authority on her people. Jimbei likewise took the position of Warlord as an act of good faith, believing it could strengthen relations between Fishman and Humans in the future.
The Seven Warlords of One Piece's actions resulted in their annulment
However, more villainous Warlords like Crocodile or Doflamingo use their position to go about their ambitions in their respective kingdoms without fear of government investigation. Even Buggy the Clown was able to make use of his new Warlord position; after the time skip, Buggy started Buggy's Delivery Service -- a mercenary guild conducted by Buggy and his crew that dispatches powerful pirates and warriors to any country or group willing to pay.
Despite the Warlords becoming almost a mainstay of One Piece, the system would eventually be nullified. At the most recent Revery, the topic was brought forth whether the Seven Warlords system should be dissolved due to the actions of Crocodile, Doflamingo and Blackbeard. It was thus decided, and all remaining Warlords were stripped of their status and their bounties reinstated in Chapter 956. Following this, Marines were deployed to all former Warlords' current locations, including Boa Hancock, Mihawk and Weevil, to either capture or eliminate their targets.