Allagion

Byzantine army
Part of a series on the

Structural history
Eastern Roman army 'Classical' Byzantine army themes tagmata Hetaireia Komnenian-era army pronoia) Palaiologan-era army allagia Varangian Guard Generals Magister militum Domestic of the Schools Grand Domestic Stratopedarches Protostrator
Byzantine navy: Greek fire Dromon Admirals (Droungarios of the Fleet Megas doux)
Campaign history
Lists of wars, revolts and civil wars, and battles (Constantinople)
Strategy and tactics
Tactics Siege warfare Military manuals Fortifications (Walls of Constantinople)

The allagion (Greek: ἀλλάγιον) was a Byzantine military term designating a military unit of 50-400 soldiers. It first appeared in the mid-to-late 10th century, and by the 13th century had become the most frequent term used for the Byzantine army's standing regiments, persisting until the late 14th century.