basically, it is safe to say that any country, who's populace was shown by history to be oppressed, the citizens were unarmed.
although life was pretty good for the average Roman, the possession of swords was strictly forbidden. they could not allow a far-off region to rise up against them, once conquered.
on to fuedal England, France, and basically every other pre-Enlightanment country of Europe. all were unarmed as the various monarchies were only interested in gaining wealth for the crowns, the people starved. a hungry mob is an angry mob! (thanks B. Marley) this in turn affected the "empires" of each sovereign. the English colonies of India, Ireland and Palestine were all unarmed, as was the French Congo of the Renaissance. the English allowed the America's to be armed as this was necessity, and the crown believed that the Brittons in America would never revolt, why would they? (hee hee!)
the first thing the Soviets did, in Ukraine anyway, was to disarm them. they knew that being fiercly independant, the Ukrainians would not support any movement towards global socialism, let alone within their boredrs. it turned out to be a smart move on the part of Stalin, who tried to wipe Ukrainians off the face of the planet through the artificial famine of 1931-1933. imagine how hard it would be to prevent a farmer from surrendering all of his crops, if he were armed!
in the later years, after all the regions and countries have been beaten, starved, deported or threatened into submission, the government realized that in the North, and especially in Siberia, Irkutsk, Yakusk and other areas West of the Urals, that guns were the only way in which the locals could eat. most were nomadic reindeer herders and huntsmen, and they never really resisted the communist ideology (actually they didn't care, as long as they could remain nomads) so they were allowed to keep their arms. what the Soviets did instead was to ban ammo for private sales. they "socialized" the ammo, and rationed out 5 rounds of ammo per season, per family.
then came Adolf's Germany. he knew what he had to do to prevent a revolt of his evil ways, and smartly banned all civilian guns in the early 1930's.
since then, Cambodia, Korea, Cuba ~ EVERY Communist country, and EVERY dictatorship has thrived on the unarmed. where there are no dictators, and no guns, the oppressors are now the common theif, gangster and druglord. just look at modern Britain, Austrailia or Kalifornia.