The two-handed sword, Zweihänder

The Zweihänder, also called bidenhänder, Zweihandschwert or Flamberge, are swords primarily used in Central and Eastern Europe during the Renaissance. 

Zweihänder swords developed from the longswords of the Late Middle Ages and became the characteristic weapon of the German Landsknechten from the time of Emperor Maximilian I (died 1519) and during the Italian Wars of 1494–1559. The Goliath Fechtbuch (1510) shows an intermediate form between longsword and Zweihänder.

This was the last phase in the trend of making very large swords, a trend that began in the 14th century and ended in the 16th century. In its developed form, the Zweihänder acquired the handling characteristics of a polearm rather than a sword due to its large size and weight, providing more striking power and greater reach. Therefore, it was not worn in a scabbard, but over the shoulder, like a pike or halberd.

The Zweihänder is a two-handed sword developed from the 15th-century longsword, but is distinctly different. As with medieval swords, there are various variants of two-handed swords. These are particularly characterized by their longer grip, allowing them to be wielded with one or two hands. 

The Zweihänder had a so-called Fehlschärfe (an unsharpened, blunt section) at the bottom of the blade, which was sometimes wrapped with leather. This allowed the right hand to be placed in front of the crossguard (thumb towards the crossguard) to perform a form of half-sword techniques. This was especially useful in a fight against pole weapons and offered the possibility to parry them. The Bolognese fencing master Achille Marozzo from the 16th century specifically demonstrates this grip in his techniques against pole weapons. Before the Fehlschärfe, the blade was equipped with so-called parrying hooks, also called parrying thorns (a kind of second crossguard) to catch the enemy weapon earlier during a weapon bind. This provided better protection for the front hand and more control over the opponent's weapon.

The grip is usually four handbreadths or longer and often divided into two parts by a thickening in the middle. The pommel is relatively small and usually pear-shaped. The crossguard is curved towards the tip and often has spiral decorations alongside oval parrying rings. The cross-section is usually round. The blade is broad with a central rib, parallel cutting edges, and parrying thorns curved towards the tip.

The Italian variant is the Spadone a due mani, or simply Spadone. It is characterized by the simpler grip and the straight crossguard with a diamond-shaped cross-section. The blade, narrowing towards the tip, often has one or more hollow lines, and the parrying thorns are straight triangles. Initially, the Spadone closely resembled a regular two-handed sword, from which it originated around the 16th century. 

Like traditional swords, Zweihänders were equipped with a pommel, grip, and crossguard. Usually, the crossguard was significantly wider than that of other swords. It was used to parry enemy strikes or even pole weapons. Zweihänders were 140 cm up to 170 cm long, with a blade up to 120 cm long. They weighed 4 to 6 kg. 

Two-handed swords emerged in the 14th century in response to improved body armor. They flourished in the late Middle Ages and became progressively longer until the well-known Zweihänder came into use during the Renaissance. They were primarily used by Landsknechts under Emperor Maximilian I. The large reach of a Zweihänder was likely advantageous against pikemen, halberdiers, lance bearers, and mounted opponents.

Landsknechts trained with the Zweihänder received the master's certificate of the long sword from the Marxbrothers (Marxbruderschaft) in late medieval Germany, received double pay, and were often called Doppelsöldner. According to research, they usually stood behind the pikemen and only entered the battle once the pike formations had already clashed. In this way, they had a similar role to the Swiss halberdiers or the Spanish targier, namely to continue the fight after the enemy formation was broken. At the same time, a unit of Doppelsöldner with Zweihänders formed the protection of the flags.

The Black Band of German mercenaries (active in the years 1510–1520) had 2,000 two-handed sword fighters in a total strength of 17,000 men. Zweihänder-bearers fought both alongside and against pike formations.

In this guard function, the Zweihänder was retained, even when it gradually disappeared from hand-to-hand combat from the end of the 16th century. The Zweihänder developed into a decorative and ceremonial weapon for bodyguards, increasingly less intended for actual combat.

Even during the Thirty Years' War and throughout the 17th century, Zweihänders were still used, but less frequently and mostly for special tasks. As late as 1711, the Venetian Giuseppe Colombani describes fencing with the large Zweihänder, which by that time could already be considered outdated.

Today, two Zweihänders are used in the Swiss Guard during the swearing-in of new recruits. The Zweihänder used in German-speaking areas, primarily by Landsknechts, were also called slachtschwerter. 

The two-handed flame sword is referred to in German as Flammenschwert (literally "flame sword"). These swords closely resemble the Zweihänders, the only difference being the design of the blade. The design of the blade is decorative but also functional, as it causes unpleasant vibrations when parrying. However, the wavy blade is not more effective at cutting than a straight one. An advantage over swords with a straight blade is that it can better distribute the force of a blow and therefore breaks less quickly. It could also intimidate the opponent in a duel and possibly discourage them from grabbing the blade. Like other Zweihänders, they were used by the Landsknechte in the 16th century.

The Bolognese Marozzo traditionally teaches the duel Spadone against Spadone in his Opera Nova of 1536, but also shows techniques against polearms to a limited extent. The weapons here are already shoulder to chin height, but do not yet have parrying rings. From the mid-16th century, the Spadone already reaches up to the crown. In later fencing schools of Italian masters such as Giaccomo DiGrassi (1570) and Francesco Alfieri (1653), it becomes clear that the purpose of use has shifted and that the Zweihänder/the Spadone from the end of the 16th century is a weapon for special tasks, particularly against multiple opponents in battle or for bodyguards.

On the Iberian Peninsula, the local variant is the Montante. This resembles the Italian Zweihänder more but is generally slightly shorter and lighter. The crossguards are usually round, and the parrying spikes, if present, are small. The Montante also had specialized use, especially by bodyguards who often had to defend against overwhelming odds. Unlike lighter blades, the Montante was frequently used in continuous circular movements. One of the most important works on the Montante is by Diogo Gomes de Figueyredo from 1651.

In Scotland, in the Highlands, the Claymore was popular as a two-handed sword variant, in the Lowlands the longer Slath sword, which resembled a slachtschwert and was equipped with side rings or a shell-shaped blade.

As Asian counterparts to the Zweihänder, the Japanese Ōdachi and the Chinese two-handed shuangshou jian can be considered.

Unlike shorter swords, such as the Katzbalger or the Swiss small sword, the Zweihänder was carried over the shoulder without a scabbard, similar to a halberd.

In the Fries Museum in Leeuwarden, a 2.13 m long and 6 kg heavy Zweihänder is exhibited, which is said to have belonged to the warrior Pier Gerlofs Donia.