A treaty between Pennsylvania and Maryland ends the Conojocular War with settlement of a boundary dispute and exchange of prisoners.

Pennsylvania, officially the Commonwealth of Pennsylvania, is a state spanning the Mid-Atlantic, Northeastern, Appalachian, and Great Lakes regions of the United States. It borders Delaware to its southeast, Maryland to its south, West Virginia to its southwest, Ohio and the Ohio River to its west, Lake Erie and New York to its north, the Delaware River and New Jersey to its east, and the Canadian province of Ontario to its northwest via Lake Erie. Pennsylvania's most populous city is Philadelphia, while the capital of the state is Harrisburg. It is the fifth-most populous U.S. state, with over 13 million residents as of the 2020 United States census, as well as being the ninth-highest by population density and the 33rd-largest state by land area. The largest metropolitan statistical area is the southeastern Delaware Valley, including and surrounding Philadelphia, the state's largest and nation's sixth-most populous city. The second-largest metropolitan area, Greater Pittsburgh, is centered in and around Pittsburgh, the state's second-largest city.

Maryland is a state in the Southern and Mid-Atlantic regions of the United States. It borders the states of Virginia to its south, West Virginia to its west, Pennsylvania to its north, and Delaware to its east, as well as with the Atlantic Ocean to its east, and the national capital and federal district of Washington, D.C. to the southwest. With a total area of 12,407 square miles (32,130 km²), Maryland is the ninth-smallest state by land area, and its population of 6,177,224 ranks it the 18th-most populous state and the fifth-most densely populated. Maryland's capital city is Annapolis, and the state's most populous city is Baltimore.

Cresap's War was a border conflict between Pennsylvania and Maryland fought in the 1730s. Hostilities erupted in 1730 with a series of violent incidents prompted by disputes over property rights and law enforcement. The conflict escalated through the first half of the decade, culminating in the deployment of military forces by Maryland in 1736 and by Pennsylvania in 1737. The armed phase of the conflict ended in May 1738 with the intervention of King George II, who compelled the negotiation of a ceasefire. A final settlement was not achieved until 1767 when the Mason–Dixon line was recognized as the permanent boundary between the two colonies.