Underhill was chartered on June 8, 1763. It is obvious in a number of the New Hampshire Grants that neither Benning Wentworth nor the grantees knew anything of the terrain with which they were dealing. The town of Mansfield was granted on the same day as Underhill, nobody having a clue that the town was bisected by the state's highest mountain. In 1839 the Legislature annexed the western section of Mansfield to Underhill, forming the present day town (it was impossible to get from one side of Mansfield town to the other). Despite the objections of residents of the eastern portion of Mansfield, who wanted to remain a separate civil entity, the Legislature saw fit to blend them with Stowe.  
The history of Underhill, Vermont : the town under the mountain, Loraine S Dwyer (1976) - find this book in a library.
FamilySearch Historical Records Collection has Vermont birth, death, and marriage records online.
The probate district for Underhill is Chittenden.
Chittenden District Probate Court
175 Main St.
PO Box 511
Burlington VT 05402
Phone: (802) 651-1518
The following is a list of major cemeteries in present-day Underhill. For location of all cemeteries, see Cemeteries of Vermont, Chittenden County, website at this link.
- St. George Village Cemetery - inscriptions at Find A Grave site.
Town Clerk Vital and Town Records, 1795-1844, can be found on FamilySearch (browse only images).
The Family History Library has microfilm of original records from the Underhill Town Clerk's Office. These include Town and vital records, 1797-Sept. 1999; indexes, 1780's-Sept. 1999.
Underhill Town Clerk
12 Pleasant Valley Rd, Underhill, VT 05489
Mailing Adress: P.O. Box 32, Underhill Center, VT 05490
Phone: (802) 899-4434
Libraries and Historical Societies
- Brief history of Underhill, VT http://www.virtualvermont.com/towns/underhill.html#about
- Town of St. George, Vermont, http://www.rootsweb.ancestry.com/~vermont/ChittendenStGeorge.html