In old records this is sometimes written Sudbury, and it may have been named for Sudbury in the county of Suffolk, England. The name of Sadsbury occurs as early as June 1, 1708 in a deed for land, but the township wasn't organized till 1717. That part of the township lying in the Great Valley was taken up at an early date in right of purchases made in England, and that part north of the valley at a somewhat later period.

In November of 1728 it was ordered that the township be divided into two townships, called East and West Sadsbury, and that the township of fallowfield may be separated from Sadsbury and made into one entire township.

Upon the erection of Lancaster County in 1729, the line between the two divisions of the township was made to conform to the county line.

In 1813 the line between Sadsbury and West Caln at its eastern end was relocated and settled. In 1825, Sadsbury was reduced in size by the formation of Valley Township, previous to which it extended eastward to the Brandywine at Coatesville.

In 1867, the township was divided by decree of court into two election districts, the Limestone Road being made the division line, and the places of voting fixed at Sadsburyville for the eastern division, and the "Swan" for the westward division.

The township was further reduced by the erection of the borough of Parkesburg, by act of Assembly in March of 1872, and by the erection of the borough of Atglen, 1875. The latter borough includes within its limits the former village of Pennington.

In 1878 the township was divided and West Sadbury erected, the line being the same that had separated the two election districts since 1867.

The early settlers were a mixture of Friends from England, and of Scotch-Irish Presbyterians. The Friends came first, and were followed by the Presbyterians.

This page updated on March 1, 2009