Polearm

A pole weapon or polearm is a close combat weapon in which the main fighting part of the weapon is placed on the end of a long shaft, typically of wood, thereby extending the user's effective range. Spears, glaives, poleaxes, halberds, and bardiches are all varieties of polearms. The idea of attaching a weapon onto a long shaft is an old one, as the first spears date back to the Stone Age. The purpose of using pole weapons is either to extend reach or to increase angular momentum—and thus striking power—when the weapon is swung.

Strengths and Weaknesses
Several characters have been seen using polearm based weapons. They offer a much more massive reach then most weapons and serve a variety of uses both offensively and defensively. The advantage they offer is a superior range in close combat to other weapons such as the sword.

However, the main offensive aspect of the weapon is on the furthest end of the pole where usually a blade is held for striking. The main offensive stance of a polearm user is therefore usually focus forward on the bladed end, the idea is to strike down the foe before they come anyway near the user and it is often difficult to change fighting stance should they lose, with the only exceptions being the staff branch of pole arms.

At its core, pole arms combatants are relatively easy to train while the weapon itself is cheap to produce.

In One Piece, polearm users have been seen mostly seen used by guards and few have been seen wielding one in battle. Unlike the sword, most uses have been just for striking or show and very few polearm based techniques have actually been featured since the most common seen wielders were background extras. Both Gol D. Roger and Noland were killed by executioners who wielded polearm based weapons.

Types of Pole Arms
Polearms are separated into different classifications by the type of tip. They vary in design from the basic fighting staves having no tips at all to the more specialised tips of the Halberds.

Staves
Staves have a variety of uses, although most are not weapon based. Only a few types of staves are counted as weapons such as the Quarterstaff and long staff. Staves are a form of Stick fighting. In some countries, stick fighting is a form of self-defense against wild animals and intruders, as everyday objects like a broom could instantly be used as defensive weapons. Stick Fighting is not a method of pole arm fighting and only fighting staves fall under the pole arm classification.

Bo
The bo (棒) is a Japanese long staff weapon which is typically around 6 ft (1.8 m) long, used in Japanese martial arts, in particular bojutsu. Related staff weapons are the jo which is 4 ft (1.2 m) long and the hanbo or hambo (half bo) which is 3 ft (0.91 m) long.

When she was first seen, Nami used a bo for fighting, this was later replaced with the Clima-Tact, although by classifications the Clima-Tact is still considered a type of bō. The Nonosama Bo, Enel's golden staff, is also a bo, albeit made from gold, and can be reforged into a trident with his Goro Goro no Mi powers.

Metal Pipe
Metal pipes can be used an improvised polearms, as demonstrated by Sabo of the Revolutionary Army who uses a metal pipe as a weapon.

Jitte
The jitte (十手) is a Japanese short staff with an extra protrusion that is specialized in disarming the opponents. Basically, it was carried by officials as a sign of position, and was as a non-sword defensive weapon, but can sometimes have a hidden blade within. A jitte is around 12 to over 24 inches long.

Smoker carries a Kairoseki-tipped jitte that is actually much longer than a normal one, and is over 83 inches long based on its name. In the anime, Commodore Kibin was seen wielding a normal jitte.

Spear
The spear (槍) was often the cheapest of the polearms to produce and at its core could be little more then a long wooden pole with a point sharpened out of the end, more advanced spears had pieces of flint or metal on the spear head. There are two types of spear; those are designed for thrusting and those that are designed for throwing. They are also amongst some of the oldest and simplest weapons in the world and have been made by humans since their early days. Spears are not just produced by humans; several species of apes were also witnessed using "spears" for hunting.

Don Krieg's Mighty Battle Spear is a giant spear with a bomb attached at the base, allowing him cause massive explosions as well as stabbing damage. Members of the Shandia tribe were seen using spears, it was particularly noted to be used by Kamakiri. The guards at Mariejois were also seen holding spears. Noland's crew were prevented from protesting their captains innocence and spears were used to keep them at bay and stop them saving their captain's life. The most notable figure with spears is Ikaros Much who wields a total of 6 spears altogether, one in each arm the spear heads actually being dried squids.

Trident


The trident (トライデント) is a particular branch of spears, usually with three prongs at the end and designed for thrusting (note; it is not a form of pitchfork nor are pitchforks counted as tridents). The trident is used both for fishing and is a military weapon. For fishing, barbed tridents are used to spear the fish on the point. For fighting, the Trident was designed to catch other types of weapons in the prongs, the idea was to first disarm the foe and once they were disarmed could then be stabbed by the trident's 3 prongs.

The trident was first introduced in the series by Enel, who forged it on the tip of his staff using his ability after realizing blunt attacks will not work on Luffy. King Neptune uses a trident, as well as Hody Jones, Prince Fukaboshi, Aladdin, the Ammo Knights and Abdullah. The Minister of the Right owns a unique bladed trident that is based on a trishula. Hatchan also owns a golden trident which was given to him by the Goldfish Princess.

Trishula
The Minister of the Right has a trishula (トリシューラ), although many tridents seen within the series have characteristics borrowed from the Trishula. This type of polearm is not intended for military use and is a Hindu-Buddhist religious symbol, the 3 tips have symbolic meanings. The middle point on the Trishula is also very distinct; it is always longer then the two side points and it will always points upwards whenever it is depicted in religious symbolism. Although it is regarded as a type of trident, unlike the trident it is also possible for the Trishula to have more than 3 spear prongs.

Lance
A lance (ランス) is a type of long spear that was traditionally used by mounted warriors such as European knights and were much heavier then other types of polearms. They were built for endurance so they did not break so easily and could not be thrown like other spear types could be. They took advantage of the horses strength and speed, they were most effective when the horse was charging, but were useless at close quarters leaving the horseback rider having to dispose of his lance to draw a sword or mace to fight with. Shura wielded a lance known as a Heat Javelin, which has a Heat Dial inside. Gan Fall also uses a lance while riding on his pet bird Pierre in his hybrid form. At Thriller Bark, some of the General Zombies were seen using lances as well. Speed Jiru was seen with a lance and a shield. Epoida was seen wielding a double headed lance.

Halberd
The halberd (ハルバード) consists of an axe blade topped with a spike mounted on a long shaft. It always has a hook or thorn on the back side of the axe blade for grappling mounted combatants. The halberd was 1.5 to 1.8 meters (5 to 6 feet) long. It is a highly versatile type of polearm and relatively cheap to produce. The point of this pole arm made it better suited for dealing with other types of pole arm. It became a favored weapon in European armies during the 15-18th century.

Bisento
A bisento (眉尖刀) is a heavy halberd, and is Whitebeard's signature weapon. The weapon's size is massive, fitting that of its owner, with a striped pole (with the stripes being all plain brown in the anime, but red and yellow in the manga) ending in a spherical edge, and a curved, large blade attached to the pole via a golden part, decorated by what looks like a sea snake, with a thin part of it protruding on the blade itself. After his death, it became his grave marker.

Naginata
A naginata (薙刀) consists of a wooden shaft with a curved blade on the end; it is similar to the Chinese Guan Dao or European glaive or Russian sovnya. Usually it also had a sword-like guard (tsuba) between the blade and shaft and was traditionally used by warriors of the Samurai class. Hannyabal's Kessui is a naginata, but was a double bladed type of naginata, which is not normal for the naginata to have; it is more of two katanas merged together by the endpoints of the hilt.

Scythe
A scythe (大鎌) is a wooden shaft (though sometimes metal or plastic) with a long, curved blade projected to the side. Due to its design, the blade only causes cutting damage by swinging, and is not meant to be used for stabbing. Scythes are meant to be used for mowing grass rather than true combat, but war scythes, which has the blades pointed upwards in a manner similar to a naginata, is more efficient.

Doc Q uses a scythe with a metal shaft, and double blades, one on opposite side of the other; a weapon worthy of his epithet, "Grim Reaper", who are traditionally portrayed as robed skeletons wielding scythes. Caribou used a simple scythe with a wooden shaft, but it was easily broken by Pekoms.

Maul
A maul (モール) is a heavy, often spiked, hammer head that is mounted on a shaft of varying lengths. They are very effective at smashing or puncturing armour, and the spiked versions were also used to drag horsemen of their mounts. Naguri was seen wielding a long-shafted maul to take down a bear, and in the past fight against other pirates. Dosun wielded a gigantic hammer that was ultimately shattered by Tony Tony Chopper.

Unidentified

 * The Alabasta guards had an unknown type of polearm which has a fan-like head. However, this does not resemble any known polearm head. The closet polearm it resembles is the Chinese monk's spade.
 * Brahm of the Tsumegeri Guards also has a strange polearm of unknown origins. The closet the tip resembles is a sasumata, which was a polearm used for catching thieves, however, Brahm's pole arm has two crescent blades that would make such an act impossible. Possibly, they are battleaxes.
 * The executioners who killed Gol D. Roger used polearms that closely resemble nagamaki, except the blade is double edged and straight.
 * Noland did not have the same type of polearm used to execute him, instead his executioners used polearms that more closely resembled glaives.

Trivia

 * At least two of the Straw Hat Pirates, Monkey D. Luffy and Nami are confirmed polearm wielders, though Luffy has since discarded using them.
 * Luffy, Ace, and Sabo all wielded polearms in their youth, although Luffy and Ace would later discarded using them when they got older preferring to fight unarmed with their devil fruit powers. Sabo is the only one of them to continue using them, even after obtaining the power of Ace's Mera Mera no Mi.