Windsor remained a part of Hellam Township until 1753 when a petition was presented to the court at York, signed by John Wright, Jr. asking that “Hallam Township be divided by a line on Stony Ridge, running across the valley to the next ridge of hills on the south side of Grist (Kreutz) Creek Valley, and also eastward along the last named ridge to the river Susquehanna.” This new township, York, included the current townships of Windsor, Lower Windsor, York and a portion of Spring Garden.

In April 1758, the following petition was presented at the April session of court: “We, your humble petitioners, hereby state that when the Townships of York and Hallam were in one, a division line was obtained which did not prove convenient or satisfactory; therefore we request that commissioners be appointed by your worshipfuls to lay off the new township.” The presiding justice, Thomas Armor, then appointed John Shultz, John Schyrack, Christian Shank and Michael Bart, to view and run the boundary line which was as follows: The name Windsor is attributed to Thomas Armor who was born in Windsor, England and was a large landowner, in addition to being the presiding justice at the creation of the township.

[5] According to the United States Census Bureau, the township has a total area of 27.2 square miles (70 km2), of which 0.04% is water.

As of the census[6] of 2000, there were 12,807 people, 4,906 households, and 3,836 families residing in the township.

17.8% of all households were made up of individuals, and 7.9% had someone living alone who was 65 years of age or older.