Line Infantry refers to the soldiers forming the bulk of any dismounted force, as distinct from Guards, light infantry and more recently, special forces.Infantry of the Line are so called because they fought in rigid formations, unlike light troops, who fought in loose order. The seventeenth and eighteenth centuries saw expansion of the roles of the infantry, and specialist grenadiers and skirmishers appeared. The Line Infantry was the remaining body of musket-armed foot soldiers.
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