The name of the state of Pennsylvania as cited on the United States Constitution is spelled incorrectly. The standard way the name is routinely written (spelled) was not done.

On the part of the Constitution where the signers affixed their names, Pennsylvania is spelled "Pensylvania," with only one "n". This was not however considered a real error. It was commonly spelled that way. In fact, it's spelled that way on the Liberty Bell. It is nonetheless spelled correctly in other instances within the US Constitution.

In 1776 spelling was not standardized. There was a general consensus on how words and names should be spelled. We find in older books that there was a tendency to spell the same word the same way, but that’s not totally true from author to author, writing in the 17th or 18th century. Even today, most of us habitually realize that we spell some words differently according to the country of origin.

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