I am not researching this family but found quite a bit of genealogy on this name in my 1886 books "History of the Susquehanna & Juniata Valleys", so am passing it on.It comes from Volume II, the Perry County chapter and is found in the pages 909 - 916.Spellings are as they appear in the book.
Louis Sponsler, who was of Germanic origin, married Tamar Evans, who was of Welsh descent.Their 6 children were: John, George, William B., Louis Jr., Margaret, and Elizabeth. The family lived in Berks County. The biography in the book concerns son William B. Sponsler, who was a brewer in Carlisle, then moved to Perry County in 1833, to New Bloomfield.William B., born September 9, 1790 in Berks, died Nov 25, 1875 in Perry.He married twice.First to Harriet Ford of Mechanicsburg in Cumberland (who died before 1827)and had 3 children: Henry L. Sponsler(moved to Augusta, Georgia) and 2 sons who died before this book was published in 1886 - Curtis F. and Charles R. Sponsler. William B.'s 2nd wife was Ann Beelman, a daughter of Christian & Catherine Beelman of Cumberland County.His 2nd wife, Ann, died March 11, 1856 and their only child was William Alexander Sponsler, who was born Jan 28, 1827 in Carlisle, Cumberland County.Son William Alexander Sponsler married Sept 4, 1851, Elizabeth F. Burkholder, a daughter of Henry L. and Margaret Burkholder of Carlisle.William and Elizabeth' children were William Henry(who married Rebecca Orr, Daughter of James and Elizabeth Orr), Annie V.(who married Charles H. Bergner of Harrisberg), and Edward R. (who married Mary Hackett, a daughter of Cadwalader J. Hackett of Altoona).