Lewisburg is a borough in Union County, Pennsylvania, United States, 30 miles (48 km) south by southeast of Williamsport and 60 miles (97 km) north of Harrisburg. In the past, it was the commercial center for a fertile grain and general farming region. The population was 5,620 at the 2000 census. It is the county seat of Union County. Located in central Pennsylvania, on the West Branch Susquehanna River, Lewisburg is northwest of Sunbury. It is home to Bucknell University and is near the Lewisburg Federal Penitentiary. Its 19th century downtown was recently placed on the National Register of Historic Places.
Lewisburg was founded in 1784 by Ludwig Derr. A settler of the area (since as early as 1763-1769), Derr had purchased several tracts of land from the William Penn family and other neighboring land owners; the largest of which was known as "The Prescott". Having been on the land for such a long time, Derr had befriended the local Native Americans of the area. Even as many of the other inhabitants routinely were sacked by Native Americans, Derr's lands remained free from attacks. Subsequently, in 1783, he worked with Samuel Weiser (son of Conrad Weiser, the famous Native Americans liaison who died in 1760, and with whose family Derr's own paternal family had been friends) to layout his combined land tracts, and create Derrstown. The name was later, after Derr's death, changed to Lewisburg.
Much has been considered regarding 'how' the name changed from Derrstown to Lewisburg. The most likely truth is that Derr's first name "Ludwig" translated into English as "Louis" but, being of German decent, it was spelled "Lewis". Later, after Derr's death, the traditional germanic "burg" was appended to his first name to create Lewisburg.