It was named after the English county of Berkshire where William Penn's family had large estates. Berkshire is often abbreviated as Berks. Reading developed during the 1740s. At that time the people living in northern Lancaster County sent several petitions requesting that a separate county be made. With the help of German immigrant Conrad Weiser, the county was formed on March 11, 1752. It was made from parts of Chester County, Lancaster County, and Philadelphia County.