- March 8, 1658 – After a devastating defeat in the Northern Wars, the King of Denmark–Norway was forced to give up nearly half his Danish territory to Sweden to save the rest.
- March 22, 1765 – The Parliament of Great Britain passed the Stamp Act, requiring that many printed materials in the Thirteen Colonies in British America carry a tax stamp (pictured).
- March 21, 1804 – The Napoleonic code, the French civil code established under Napoleon, entered into force, eventually strongly influencing the law of many other countries.