Complex sentence: The gallowglass were attractive as a heavy armour trained aristocratic infantry to be relied on as a strong defence for holding a position, unlike most Irish foot soldiers, who were lower class and less well armoured than the typical Irish noble who fought as cavalry.
Split into simpler sentences: The gallowglass were attractive as a heavy armour trained aristocratic infantry to be relied on as a strong defence for holding a position. Unlike most Irish foot soldiers, who were lower class and less well armoured than the typical Irish noble who fought as cavalry.