National debt is the total amount amount of money that a government has borrowed. National deficit is total of all previous annual government deficits. Keep in mind that a deficit is the difference between what a government takes in and what it spends. The two are related because when the government is unable to fully repay any debt it has accrued that money becomes a part of the annual national deficit. So as the amount of national debt increases so does the amount of national deficit.
The reason why earlier historians consider the medieval periods the "dark ages: is : the era seemed less important than the renaissance and the roman empire
there was no significant societal progress during this age
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