Dom Pedro I, the founder and first ruler of the empire of Brazil, declared Brazil’s independence from Portugal.
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El Salvador established Bitcoin as legal tender.
The Great Atlantic hurricane formed and wreaked havoc for a whole week.
The Treaty of The Hague was signed between the German Empire, Great Britain, and The Netherlands.
Edith Eleanor McLean became the first baby ever to use an incubator.
Boston, Massachusetts, was founded by Governor Winthrop.