Present-day Middlesex County was at first included in Lancaster County and parish. A few years after 1666, the parish was divided into two parts: Christ Church, Lancaster and Christ Church, Middlesex. Sometime before 1666, that parish was divided into two portions and the new parishes were named Lancaster and Pyanketank. In 1666, they were reunited under the name of Lancaster, but a few years later were again separated and acquired the organization which they retained through the colonial period as Christ Church, Lancaster and Christ Church, Middlesex.
The parish register of the latter, containing the baptisms, marriages, and burials of thousands of communicants during the years 1653-1812, is reprinted in this book. No register of Christ Church, Lancaster survives, and the extant vestry book covers only the years 1739 to 1786. Hence, the great importance that attaches to the register of Christ Church, Middlesex.