Maryland had long practiced an uneasy form of religious tolerance among different groups of Christians.
In 1649, Maryland passed the Maryland Toleration Act, also known as the Act Concerning Religion, a law mandating religious tolerance for trinitarian Christians.
Passed on September 21, 1649, by the assembly of the Maryland colony, it was the first law requiring religious tolerance in the British North American colonies.

The Calvert family, who had founded Maryland partly as a refuge for English Catholics, sought enactment of the law to protect Catholic settlers and those of other religions that did not conform to the dominant Anglicanism of England and her colonies.
Maryland had long practiced an uneasy form of religious tolerance among different groups of Christians. In 1649, Maryland passed the Maryland Toleration Act, also known as the Act Concerning Religion, a law mandating religious tolerance for trinitarian Christians. Passed on September 21, 1649, by the assembly of the Maryland colony, it was the first law requiring religious tolerance in the British North American colonies.
The Calvert family, who had founded Maryland partly as a refuge for English Catholics, sought enactment of the law to protect Catholic settlers and those of other religions that did not conform to the dominant Anglicanism of England and her colonies.
Protestant Revolution (Maryland)