Complex sentence: Despite their lack of numbers and poor tactical situation Mar's army continued to fight through the day and inflicted great losses upon the highlanders and it earnt its traditional designation, Red Harlaw, as a result of the fierceness of the fighting.
Split into simpler sentences: Despite their lack of numbers and poor tactical situation Mar's army continued to fight through the day and inflicted great losses upon the highlanders. The contest earnt its traditional designation, Red Harlaw, as a result of the fierceness of the fighting.