Cumberland County, Pennsylvania was created on January 27, 1750 from Lancaster County and unorganized areas of the Commonwealth of Pennsylvania. Cumberland County is a county located in the U.S. state of Pennsylvania and is one of three counties comprising the Harrisburg–Carlisle Metropolitan Statistical Area. As of 2004, the population was estimated at 221,397. According to the U.S. Census Bureau, the county has a total area of 551 square miles, of which, 550 square miles of it is land and 1 square miles of it (0.18%) is water.

Cumberland County was named after Cumberland, England. Its county seat is Carlisle. The county also lies within the Cumberland Valley adjoining the Susquehanna River at its eastern border, stretching approximately 42 miles from the borough of Shippensburg on the west to the Susquehanna River in east Cumberland County.

Cumberland County was first settled by a majority of Scotch-Irish immigrants who arrived in this area in about 1730. It has been estimated that English and German settlers constituted about ten percent of the early population. Originally the area was mostly devoted to farming, later developing other trades.

These settlers built the Middle Spring Presbyterian Church in 1738 near present day Shippensburg, Pennsylvania. It is one of the oldest churches in central Pennsylvania.

The oldest towns in the county are Shippensburg and Carlisle, and although both were settled in the 18th century, they each have their own unique history. Shippensburg is home to Shippensburg University of Pennsylvania, one of 14 universities of the Pennsylvania State System of Higher Education. The United States Army War College is a United States Army school located in Carlisle, Pennsylvania, on the 500 acre campus of the historic Carlisle Barracks, a military post dating back to the 1770s. It caters to high-level military personnel and civilians and prepares them for strategic leadership responsibilities. It is the U. S. Army's most senior military educational institution. Carlisle is also home to Dickinson College, established in 1773, as well as the Penn State Dickinson School of Law.