[Research Guidance: Denmark - Research Outline] Research Guidance Version Of Data : 6/8/2001: "In Denmark, a person did not become a citizen by virtue of birth. Citizenship was a valuable privilege that included:-

Rights to engage in business in a city.
Protections under the law.
Permission to reside in a city without being expelled.

Citizenship was extended by individual cities to some of their inhabitants, primarily those who wanted to engage in business, and did not pertain to the country as a whole.

Those who received the rights to citizenship were recorded in citizenship books
[Borgerskabpprotokoller ???]. "
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