Thanks to Kenneth Forbes for submitting this information, extracted from Massachusetts Genealogical Research by George K. Schweitzer (1990)
Hampshire County, prior to becoming Hampden Co., was established in 1662. The county seat in Hampshire County, from 1662-1812 was Springfield.
Deeds - Rgistered at Springfield during this time, and also at Northampton for 1787, and Deerfield (now in Franklin County,) fro 1787-1812. The deeds registered at Deerfield were transferred to Greenfield in 1812.
Other Records - The following records are to be found in the court records of the towns of Springfield and Northampton: