The weapons of the Byzantine Empire are often overlooked. In particular, their two types of swords are forgotten: the spathion and the paramerion. Both of these swords started to appear in the 8th century and continued on until the empire's fall in 1453. Here is a brief overview.
Spathion
The spathion was an evolved form of the Roman spatha. The word itself is the Greek form of "spatha". The appearance is most likely why it has been forgotten as it can be visually indistinct from arming swords. The hilts consist of simple cross guards and often have a ball pommel but other pommel styles existed. The blades varied, but were straight and double-edged with a balance of cut and thrust.
Paramerion
The paramerion was developed from the sabres of the Avars in the 7th century. The hilts mirror that of the spathion consisting of a simple cross guard and ball pommel. Later hilts mirror Arabic hilts. The blades are single-edged and curved.
Bonus: Rhomphaia
The rhomphaia was originally a Thracian two-handed sickle sword, meaning the blade was slightly curved (though less than that of the Dacian falx) with the edge on the inside of said curve. In the Byzantine context it is simply a two-handed version of the paramerion and sometimes the spathion.
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