author
A Civil War veteran and regimental historian, he wrote from firsthand experience about the First Delaware Volunteers and the long arc of their service. His work preserves the voice of soldiers who fought in the Union army, blending memory, detail, and veteran testimony.
William P. Seville, also known as William Penn Seville, is best known for History of the First Regiment, Delaware Volunteers, from the commencement of the "three months' service" to the final muster-out at the close of the rebellion, published in 1884. The book was prepared at the request of surviving members of the regiment, and Seville was a natural choice to write it because he had served with the unit himself.
Contemporary and later references identify him as a captain and as an original adjutant of the First Delaware Volunteers. That firsthand connection gives his writing much of its value: it is not just a formal history, but a record shaped by someone who knew the regiment from the inside.
Reliable biographical detail beyond his military service and authorship was limited in the sources I could confirm here, so this overview stays close to what is well supported. What clearly stands out is his importance as a witness to the Civil War experience of Delaware soldiers and as a keeper of their story.