Why does Massachusetts have a strange notch in Connecticut? The history of the Southwick Jog

Near Southwick, Massachusetts extends south into Connecticut in a small projection known as the Southwick Jog. The notch grew out of a faulty colonial survey, disputes over established towns and a compromise reached in 1803–1804. It was a negotiated settlement over land and jurisdiction, not a deliberate decorative exception to an otherwise straight border.

The Strange Geography of the Southwick Jog

The northern boundary of Connecticut appears relatively simple on most maps. Beginning near the New York state line, it extends eastward across southern New England, separating Connecticut from Massachusetts. Although small irregularities exist, the general impression is of a straight line dividing two neighboring states. Near Southwick, however, the boundary makes an abrupt turn southward, continues for approximately two and a half miles, and then returns northward. The resulting projection forms a nearly rectangular piece of Massachusetts surrounded by Connecticut on three sides. The territory lies between the Connecticut towns of Suffield to the west and Granby to the east. It forms the southernmost part of Southwick, a Massachusetts town located south of Westfield and near the Congamond Lakes.

Colonial Charters and the Rival Claims of Massachusetts and Connecticut

Massachusetts and Connecticut developed as separate English colonial settlements during the seventeenth century. Their political origins were closely connected to Puritan migration, but their governments emerged under different institutional arrangements. The Massachusetts Bay Colony received its royal charter in 1629. Its southern boundary was described partly through a line extending westward from a point three miles south of the southernmost part of the Charles River. This definition appeared straightforward, but it depended on accurately identifying the relevant geographical point and extending a line across territories that had not been systematically surveyed. The English settlements that eventually formed Connecticut developed farther south along the Connecticut River and the Long Island Sound coast. Towns such as Hartford, Windsor and Wethersfield established political institutions of their own, while the surrounding region contained Indigenous communities whose territorial relationships predated European settlement.

Springfield offers an example of these overlapping claims. Founded in the 1630s by William Pynchon and other English settlers, it initially possessed strong connections with the Connecticut River settlements farther south. However, political and commercial disagreements encouraged Springfield to align with Massachusetts. The decision had lasting geographical consequences. Springfield became an important Massachusetts settlement on the Connecticut River, strengthening Massachusetts's claim to territory farther south and west than Connecticut leaders considered appropriate.

As the colonies expanded, establishing the northern boundary of Connecticut became increasingly important. Massachusetts officials therefore organized a survey intended to determine where their southern territorial limit should lie.

The Surveying Mistake of 1642

In 1642, Massachusetts appointed Nathaniel Woodward and Solomon Saffery to determine the colonial boundary. Their task was to locate the line established by the Massachusetts charter and extend it westward. The surveyors faced considerable practical difficulties. New England contained extensive forests, rivers, wetlands and relatively few established roads. Accurately maintaining a line of latitude across such terrain required instruments, astronomical knowledge and surveying methods that were not always available or consistently applied. Woodward and Saffery adopted an unusual approach. Rather than continuously surveying the boundary overland, they traveled by water around Cape Cod and into the Connecticut River system before attempting to establish the line farther inland.

Their measurements were inaccurate. The line they identified lay approximately seven or eight miles south of the boundary implied by the Massachusetts charter. Massachusetts accepted the survey as an authoritative interpretation of its southern frontier. Connecticut, however, disputed its accuracy and maintained that the line had been placed too far south.

The disagreement became more serious as settlements expanded into the affected region. Towns established under Massachusetts authority found themselves within areas that Connecticut considered part of its rightful territory.

Why Connecticut and Massachusetts Fought Over Entire Towns

During the late seventeenth century, Connecticut attempted to establish a more accurate version of the boundary. A new survey was carried out in 1695, and further joint surveying work followed in 1702. These investigations supported Connecticut's argument that the original Massachusetts survey had placed the line too far south. However, Massachusetts was reluctant to surrender territories that had already been settled and administered under its authority. The dispute particularly affected Suffield, Enfield, Somers and Woodstock. These communities had developed strong connections with Massachusetts, but their geographical positions made them subjects of Connecticut's competing territorial claim.

The interests of the inhabitants did not necessarily coincide with the preferences of either colonial government. Local communities considered taxation, political representation and the convenience of administrative relationships when deciding which colony they preferred. In 1713, Massachusetts and Connecticut reached an agreement intended to settle the matter. Connecticut accepted a financial arrangement under which Massachusetts retained the disputed territory. However, the settlement did not enjoy universal local support. Some residents continued to believe that Connecticut offered more favorable political and economic conditions. The conflict revived during the following decades. In 1749, Connecticut formally accepted Suffield, Enfield, Somers and Woodstock into its jurisdiction, challenging the earlier agreement and provoking renewed objections from Massachusetts.

Residents had established farms, churches, property arrangements and local institutions under particular colonial authorities. Changing the political boundary could alter taxes, courts, representation and public obligations.

Southwick and the Emergence of the Notch

Southwick originally developed as a southern section of Westfield, Massachusetts. Its settlement was associated with agricultural expansion into the lands west of the Connecticut River valley. The area contained farms, woodlands and the Congamond Lakes, a group of lakes that later became important geographical reference points in the boundary dispute. As the settlement grew, Southwick acquired a more distinct local identity. It was established as a district separate from Westfield in 1770 and subsequently developed its own municipal institutions.

However, the southern portion of Southwick lay within the area affected by the unresolved Massachusetts–Connecticut boundary disagreement. In 1774, part of southern Southwick came under Connecticut's jurisdiction and was associated with the town of Simsbury. This change reduced the territory administered as part of Southwick and created new questions about the political position of local residents. The timing was especially significant. The American Revolution began the following year, transforming the English colonies into independent political communities. Yet the removal of British authority did not automatically resolve the territorial disagreements that had developed under colonial rule.

When Connecticut and Massachusetts became states within the new United States, they inherited the old controversy. In 1786, the Connecticut town of Granby was formed from part of Simsbury, and the disputed southern Southwick territory became associated with the new municipality.

The Congamond Lakes became particularly important in the eventual settlement because they provided a recognizable geographical feature through which the disputed territory could be divided.

The Compromise of 1804

The two states appointed commissioners to investigate disputed sections of the frontier, examine earlier surveys and develop an acceptable political compromise. During the 1790s, negotiations addressed the long-standing inconsistencies between the intended colonial boundary and the territories actually administered by the neighboring governments. The Southwick area remained particularly contentious. Massachusetts argued that it deserved territorial compensation for lands and settlements it had relinquished elsewhere along the border. Connecticut maintained that the proper boundary should correspond more closely to the original charter provisions.

A compromise gradually emerged during 1803 and 1804. The disputed Southwick territory was divided, with the area east of the Congamond Lakes remaining under Connecticut's jurisdiction and the western portion being assigned to Massachusetts. The resulting boundary preserved a small southward extension of Massachusetts territory. Instead of following the otherwise nearly straight interstate line, the border turned southward around the land retained by Massachusetts and then returned northward.

Even after the Southwick settlement, a few other boundary questions remained. The final significant adjustment along the Massachusetts–Connecticut frontier occurred in 1826, when the states resolved a small irregularity near the Union and Woodstock area.

Why the Border Was Never Straightened

Interstate borders are not determined solely by cartographic convenience. They are legal boundaries established through historical agreements, legislation, surveys and administrative practice. Once Massachusetts and Connecticut accepted the compromise of 1804, the unusual line acquired legal significance. The land within the projection became part of Massachusetts, and local institutions developed accordingly. Straightening the boundary would require another political agreement transferring territory from Massachusetts to Connecticut. Such a change would also involve questions concerning property, taxation, municipal administration and the legal rights of affected residents.

Because the area is small and the border causes relatively few serious administrative problems, neither state has possessed a compelling reason to reopen the settlement. Its existence has also become part of local historical identity. Residents and visitors sometimes refer humorously to the idea of Connecticut recovering the lost territory, while the projection remains a recognizable geographical feature in regional maps.

The Congamond Lakes make the arrangement especially noticeable. Their waters and surrounding recreational areas lie close to the interstate boundary, creating situations in which ordinary local activities take place near an irregular political division. Nevertheless, the border does not function as an international frontier. People travel freely between Massachusetts and Connecticut, and the two states cooperate within the broader constitutional framework of the United States.

What the Southwick Jog Reveals About American State Borders

Later measurements could show where earlier surveyors had gone wrong, but they could not undo the towns, property rights and political loyalties established in the disputed area. The states settled those competing interests through agreement, leaving a bend around Southwick rather than extending one straight line across the whole frontier.

That settlement remains the operative boundary. Straightening it now would require another transfer of jurisdiction and agreement over the affected land, with little practical benefit for residents who already cross the state line routinely.