Township Number Four in the first range north of the Waldo Patent, now the town of Troy, which had been crossed by the western line of Hancock County, was entirely set off to Kennebec County, February 28, 1799 (ch. 72): The western boundary was further adjusted by the annexation from Somerset County of Township Number Four in the fifth range north of the Waldo Patent (now Dexter) in 1811 (ch. 36); and Township Number Four in the sixth range (Sangerville) in 1812 (ch. 4); Township Number Four in the fourth range was set off to Somerset County in 1813 (ch. 85).
The northern part of Hancock County, lying north of the north line of Waldo Patent on the west side of Penobscot River; and on the east side of said river north of a line beginning at the river at the southwest corner of Orrington and extending along the south side of Orrington, Brewer and the gore east of Brewer to the west line of Bingham’s Penobscot Purchase, to the northwest corner thereof; thence easterly on the north line of the Purchase townships to the line of Washington County, was set off to form the new county of Penobscot, April 1, 1816 (ch. 121).
Two adjustments in this new northern boundary were made the same year: land was set off from Buckstown to Orrington (ch. 13), and one estate, from the town of Frankfort, was set off to Hampden (ch. 14).
All of Hancock County lying west of Penobscot River and Bay was set off to form part of the new county of Waldo, July 3, 1827 (Public Laws, chs. 354, 362).
Three townships on the east boundary – number four, North Division, and numbers forty-one and thirty-five of the Middle Division – were annexed from Washington County in 1851 (ch. 154).
A strip 2 miles wide and 6 miles from east to west, lying north of township number two (Grand Falls Plantation) was set off to Burlington in Penobscot County in 1835 (ch. 559).
The town of Vinalhaven, which was made up of a group of islands in Penobscot Bay, was set off to Waldo County in 1838 (ch. 451).
Page’s Mills Settlement, a strip 2 miles wide lying north of township number one, North Division, was set off to Lowell in Penobscot County, February 20, 1841 (ch. 102). A tract was set off from Bucksport and Dedham to the town of Brewer, April 10, 1841 (ch. 161).
Matinicus Island was set off to Lincoln County in 1843 (ch. 118).
The Hancock-Washington line was altered, March 12, 1844, by extending the boundary from the northeast corner of Gouldsborough southeasterly and southerly by the middle channel of Gouldsborough Harbor to the ocean (Public Laws, ch. 99).
Land was set off from Bucksport to Orrington in Penobscot County in 1850 (ch. 376).
The remaining islands of the Matinicus group – Hacketosh, Wooden Ball, Nomansland, Two Bush, Ten Pound, and Matinicus – were set off to Lincoln County in 1852 (ch. 578).
The town of Greenfield and townships number one and two of the North Division were set off to Penobscot County in 1858 (ch. 198).
The town of Isle au Haut was set off to Knox County, March 12, 1913 (ch. 83).
The county of Hancock now contains the city of Ellsworth; the towns of Amherst, Aurora, Bar Harbor, Bluehill, Brooklin, Brooksville, Bucksport, Castine, Cranberry Isles, Dedham, Deer Isle, Eastbrook, Franklin, Gouldsboro, Hancock, Lamoine, Mariaville, Mount Desert, Orland, Otis, Penobscot, Sedgewick, Sorrento, Southwest Harbor, Stonington, Sullivan, Surry, Swan’s Island, Tremont, Trenton, Verona, Waltham, and Winter Harbor; the plantations of Long Island, Osbor, and Number Thirty-three; 14 townships and 21 islands classed as wild lands.