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A Line Between North & South

When you hear this title, what picture comes to mind? Soldiers in blue and gray uniforms? Red barns in the middle of fields? Sweet tea? Split rail fences?

One line would come to represent the dividing line between North and South, Slave and Free. The Mason Dixon line (also known as the border between Maryland and Pennsylvania) has a rather interesting history!

King Charles I of England gave a charter for the land - now known as Maryland - to Cecilius Calvert, the second Lord Baltimore, in 1632. Maryland's boundaries were described as beginning "at the 40 degree north latitude line; in the south by the Potomac River and the latitude through Watkins Point on the Eastern Shore; in the east, the Atlantic Ocean; and, in the west, by a meridian through the source of the Potomac River. Three of these borders were created by natural landmarks and were easy to determine exactly when Calvert's land began." (1)

Yet Maryland's northern boarder was not so clear. In 1681, King Charles II bestowed the charter for the land - named Pennsylvania - to William Penn. Pennsylvania's northern boarder is at the "43 degree north latitude line"; westward until "the land reached until a meridian five degrees west of the Delaware Bay; and in the east, the boundary was marked by the Delaware Bay." (1)

"The southern boundary extended eastward along the fortieth parallel of north latitude until it intersected an arc extending in a 12-mile radius from the courthouse in New Castle, which is now in Delaware. However, the 40 degree latitude line and the circle do not intersect anywhere - in fact, at the closest point, they were 13 miles away. This created what has now been dubbed "The Wedge," although that land is now considered to be part of Delaware.

The dispute between the Penns and the Calverts began because they both claimed the land between the 39th and 40th parallels according to the charters granted to each colony. One of the reasons why this land dispute was so heated is that the historic city of Philadelphia falls within the disputed territory and both states wanted to claim the landmark as their own." (1)

Charles Mason and Jeremiah Dixon were British astronomers and surveyors who were sent to survey the land. They arrived in Philadelphia, Pennsylvania on 15 November 1763 and began work on the 6th of the next year. Their work built on the work of David Rittenhouse, the first director of the U.S. Mint, who had worked to on this line in 1763. Mason and Dixon were only going as far as the Susquehanna River (in 1765). However they didn't stop there, during the next two years Mason and Dixon would draw their line eastward to the Delaware River (1766) and westward to the Allegany mountains (1767).

"According to the diplomatic agreement between Iroquois and British diplomats, the Iroquois would ultimately decide where the survey ended. In July members of the Indian delegation and apprehensive laborers deserted after the group encountered an Iroquois war party headed south. At Dunkard Creek (today just west of Route 79 in Greene County) the Iroquois contingent refused to permit Mason and Dixon to continue any farther. On October 9, after close to four years of work, the survey ended, some 233 miles from “the Post mark’d West” and short of what is today Pennsylvania’s western boundary." (2)

Then as the country grew, the Mason Dixon line became known not just as the division between Maryland and Pennsylvania, but as the dividing line between north and south. This started during the end of the Revolutionary War, when Pennsylvania abolished slavery.

"The first step came on March 1, 1780, when Pennsylvania abolished slavery — and the longest section of the 12-year-old line, about 233 miles long, became the boundary not just between Pennsylvania and Maryland, but between freedom and slavery." (3)

Yet it would not gain the significance of being the dividing line between north and south until the Missouri Compromise of 1820. This Compromise led to a dividing line between which states would enter as free and which as slave. Yet, the Mason Dixon line became only a goal to reach for those reaching for their freedom. This border is one that Harriet Tubman along with many other slaves crossed in order to gain their freedom in Pennsylvania and points northward.

For those living outside of Maryland, this line has somewhat faded into history, however those in Maryland still feel strongly that this line divides the north and south culturally. Having grown up in both Tennessee and Maryland, I personally feel that this is only the border between two states. However, some locals have a different opinion. Some in Maryland think they are southerners, just because they live south of the Mason Dixon line.

Understanding the background behind the lines that draw our country into existence is important. This is one of the many reasons to study history - to better understand the reason for decisions others have made, and the effects they can still have on our lives today.

Mason Dixon line map from the Library of Congress, Geography and Map Division



Fine Books & Collections ~ Walk the Line

History Today ~ The Mason Dixon Line

Maryland Office of Tourism ~ Mason & Dixon

National Archives: DOCSTeach ~ Journal of Charles Mason and Jeremiah Dixon (This is the journal that Mason and Dixon recorded all their findings in!)

National Archives: Founders Online ~ To George Washington from Mary Mason, 30 March 1790

Princeton University ~ A Republic in the Wilderness: Treasures of American History from Jamestown to Appomattox - “A Plan of the Boundary Lines…between the Provinces of Maryland and Pennsylvania,” 1768.


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