More than a few medieval­ists object to the term “Dark Ages” as applied to the peri­od in which they spe­cial­ize. That can seem wish­ful in light of most com­par­isons between medieval times and the Renais­sance that came after­ward, or indeed, the era of the Roman Empire that came before. Con­sid­er the state of Europe as the fourth cen­tu­ry began: “The great cities of antiq­ui­ty were depop­u­lat­ed, some left in ruins,” says the nar­ra­tor of the How So video above, telling the sto­ry of the con­ti­nen­t’s polit­i­cal and lin­guis­tic frag­men­ta­tion. “The Roman trans­porta­tion sys­tem decayed, erod­ing com­mu­ni­ca­tion and long-dis­tance trade. Coins van­ished, leav­ing no eco­nom­ic sys­tem to sup­port pro­fes­sion­al armies. Lit­er­a­cy plum­met­ed, crip­pling admin­is­tra­tive sys­tems. And most notably, peace and secu­ri­ty were gone.” But there’s plen­ty more his­to­ry to come there­after: about a mil­len­ni­um’s worth, in fact, which the video cov­ers in a mere twen­ty min­utes. Events of note in that grand sweep include Jus­tin­ian I’s attempt to expand the Byzan­tine Empire of the east; the cre­ation and spread of the Islam­ic caliphate; Charle­mag­ne’s uni­fi­ca­tion of …