It is less dangerous to arm slaves in a monarchy than in republics. There, a warlike people and a body of nobility will adequately contain those armed slaves. In the republic, men who are merely citizens will be quite unable to contain men who, with arms in hand, will find themselves the equals of citizens.
The Goths who conquered Spain spread throughout the country, and soon found themselves very weak. They enacted three considerable ordinances : they abolished the former custom forbidding them to ally by marriage with Romans  ; they decreed that everyone exempt from taxation would go to war, on pain of enslavement  ; and they ordered that every Goth would lead into war and arm the tenth part of his slaves.  This was not a very great number in comparison with those who remained. Moreover, these slaves led into war by their master did not constitute a separate corps : they were in the army, and remained, so to speak, in the family.