As a direct result of the population pressure in Massachusetts Bay arising from the increase in the migration rate in the mid-1630s, and as a side effect of the narrow doctrinal differences among some of the leading ministers, settlements were begun at three places along the Connecticut River. These three settlements grew into the towns of Hartford, Windsor, and Wethersfield. Even as this demographic movement was taking place, Saybrook, a fortified village, was being built at the mouth of the Connecticut.
Further migration produced new towns along both sides of Long Island Sound (some interspersed with the towns aligned with New Haven Colony, see the following section entitled 'New Haven'). In 1645, Pequot was settled further to the east along Long Island Sound on the mainland and was soon renamed New London.
From the earliest days, the towns maintained all land records, including proprietoral grants and deeds from one person to another. At the same time, until the absorption of New Haven Colony, all probates were centrally recorded. In 1666, just four years after the receipt of the royal charter and the incorporation of New Haven Colony, four county courts were established: Hartford, Fairfield, New Haven, and New London. These counties (along with four others created in the eighteenth century) remained the creators of the usual run of civil and criminal court records. Over the decades, however, probate jurisdiction was divided and subdivided, to the point that there were more than a hundred probate districts, many of them containing only one town or city.
The system of probate districts in Connecticut is unlike that in any other colony or state. Neighboring Rhode Island handled probate matters at all times at the town level. Vermont, many of whose earliest settlers came from Connecticut, eventually divided some of its counties into districts for probate purposes, but these districts, once established, did not change in size.
As noted previously, soon after the union of Connecticut and New Haven colonies, four counties were established: Hartford, Fairfield, New Haven, and New London. Throughout the rest of the seventeenth century, the courts of these counties also handled probate matters. In 1719 the legislature began the process of dividing the counties into smaller probate districts, creating Guilford, Windham, and Woodbury districts. From this date forward, the researcher must look in the towns for land records, in the districts for probate records, and in the counties for court records.
By the time of the Revolution, there were twenty probate districts in Connecticut. The last of these erected in colonial times was Westmoreland District, created in May 1775, considered to be derived from Litchfield District. Westmoreland was actually in Pennsylvania, in territory claimed by Connecticut and formally ceded to Pennsylvania in 1782.
The probate records for the Hartford District from 1635 to 1750 have been published by Charles William Manwaring as Early Connecticut Probate Records.<ref>Charles William Manwaring, Early Connecticut Probate Records, 3 vols. (Hartford, 1902'06).</ref> Since these published records begin in 1635, and Hartford County (and therefore the associated probate district) was not established until 1666, it is clear that the earliest of these documents must have been recorded somewhere besides Hartford County. Manwaring, in fact, took them from a number of sources. Some of the earliest are found in the records of Connecticut Colony.
The bulk of the probate records for the Hartford District down to 1700 were recorded in six volumes. Each volume was a double volume. One side contained the records of the Hartford County court, and the reverse side, with separate pagination, contained the probate records. However, the 'court side' also included probate proceedings, such as letters of administration. Thus, in the published version of these records, the proceedings for any given estate might include material from both the 'court side' and the 'probate side' of the same volume. Furthermore, if the administration of a given estate lingered for some years, some of the documents might have been included in one of the later manuscript volumes but would be entered out of place in the published volume, along with the earlier documents. In addition, when the only surviving version of a given document is in the loose papers, these items are also gathered in the printed version along with the records from the court volumes. The transition to the records of Hartford County, as established in 1666, takes place in the middle of the third of these manuscript court volumes, which covers the years from 1663 to 1677.
The towns of New Haven, Milford, and Guilford, close to one another along Long Island Sound, were all organized in 1639 as independent plantations. As the formation of the Confederation of New England loomed imminent in 1643, these three towns, along with Southold on Long Island, joined together as the colony of New Haven. A few other towns on either side of Long Island Sound joined this colony in the years following. Finally, in 1662, when Connecticut Colony finally acquired its own charter, New Haven Colony agreed to merge with Connecticut to form one government.
In addition to the usual range of town records, New Haven Colony held its own courts, the records of which have been published in Charles J. Hoadly's Records of the Colony and Plantation of New Haven, From 1638 to 1649, and Records of the Colony or Jurisdiction of New Haven, from May, 1653, to the Union.<ref>Charles J. Hoadly, Records of the Colony and Plantation of New Haven, From 1638 to 1649 (Hartford, 1857); Records of the Colony or Jurisdiction of New Haven, from May, 1653, to the Union (Hartford, 1858).</ref> Because there were so few towns in the colony, and because of the preeminence of the town of New Haven itself, these colony records sometimes seem more like New Haven town records.
As with Connecticut Colony, the New Haven towns kept their own land records. An interesting document contains some of the earliest records of this sort for the town of New Haven. Entitled 'A Book of All the Lands which Planters at First or by Alienations Since Possess Within New Haven Town,' this volume does not reside with the other town records, but is available on microfilm at the New Haven Colony Historical Society. Compiled in 1645 and 1646, the volume recapitulates an earlier list of estates, which in effect lists all the proprietary shares in the town. The clerk who prepared the volume also used it to calculate the annual taxes on this land and to record some of the later sales of this land by the original proprietors or their successors. Thus, this one volume, for a space of about a decade and a half, served three functions: proprietors' record, tax list, and deed register. In about 1659, entries ceased to be made in this record book. Instead, a regular deed register was begun, the tax records were kept separately, and eventually a separate set of proprietors' records was begun.<ref>Great Migration Newsletter 13 (2004): 3'7, 9'16, 19'21.</ref>
Gale Ion Harris, 'Captain Richard Wright of Twelve-Mile Island and the Burnhams of Podunk: Two Seventeenth-Century Connecticut River Families,' American Genealogist 67 (1992): 32'46.
Gale Ion Harris, 'The Children of Joseph and Mary (Stone) Fitch of Hartford and Windsor, Connecticut,' American Genealogist 68 (1993): 1'10, 95'105. In each of these articles, Harris combines data from church, court, and medical records with a deep analysis of entire neighborhoods to unravel a number of difficult genealogical networks.