Hadley is a town in Hampshire County, Massachusetts. The population was 4,793 at the 2000 census. It is part of the Springfield, Massachusetts Metropolitan Statistical Area. The area around Hampshire Mall and Mountain Farms Mall along Route 9 is a major shopping destination for the surrounding communities.
Hadley was first settled in 1659 and was officially incorporated in 1661. Its settlers were primarily a discontented group of families from the puritan colonies of Hartford and Wethersfield, Connecticut, who petitioned to start a new colony up north after some controversy over doctrine in the local church. At the time, Hadley encompassed a wide radius of land on both sides of the Connecticut River (but mostly on the eastern shore) including much of what would become known as the equivalent lands. In the following century, these were broken off into precincts and eventually the separate towns of Hatfield, Amherst, South Hadley, Granby and Belchertown. The early histories of these towns are, as a result, filed under the history of Hadley.
Edward Whalley and General William Goffe, two Puritan generals hunted for their role in the execution (or "regicide") of Charles I of England, were hidden  in the home of the town's minister, John Russell. During King Philip's War, an attack by Native Americans was, by some accounts, thwarted with the aid of General Goffe. This event, compounded by the reluctance of the townsfolk to betray Goffe's location, developed into the legend of the Angel of Hadley, which came to be included in the historical manuscript "History of Hadley" by Sylvester Judd.
In 1683, eleven years before the Salem Witch Trials, Mary Webster, wife to William Webster son of the former governor of Connecticut and a founder of the very town of Hadley John Webster, was accused and acquitted of witchcraft. She was unsuccessfully hanged by rowdy town folk. A description is given in Cotton Mather's Magnalia Christi Americana.
The Civil War general Joseph Hooker was a longtime resident of Hadley. Levi Stockbridge, one of the founders of the Massachusetts Agricultural College (now the University of Massachusetts Amherst), was also from Hadley where he was a farmer.
Hadley's transformation from an old agricultural order to the new form is the direct result of expansion of the nearby University of Massachusetts Amherst during the 1960s. Much of its former farmland was swallowed in the housing market stimulated by incoming faculty and off-campus students. Route 116 was redirected in an attempt to solve traffic congestion. Route 9, which runs east-west through the town to connect Amherst and Northampton, became a hotpoint for commercial development, and large corporations such as Stop & Shop and McDonald's opened stores along the strip. Today, the Hadley economy is a mixture of agriculture and commercial development, including big-box stores and the Hampshire Mall. Recently announced development plans included a Wal-Mart Supercenter, a Home Depot and a Lowe's, plus more than a dozen other stores. These stores cut through a bison farm, angering some. Residents recently passed a limit on retail store size at , but it will not affect these large projects.
In 2003, an organization called Hadley Neighbors for Sensible Development was formed that has opposed continued large scale commercial development in Hadley by emphasizing the down side of such growth. However, many local residents support commercial development and about 1,000 people signed a petition asking for a new Wal-Mart saying it would save them money on their groceries. In 2008, Wal-Mart pulled its plans to build the Supercenter after the Conservation Commission ruled that the plan did not comply with wetlands regulations. The developer of the site (Hampshire Mall) has filed and lost numerous appeals but continues its legal challenges of the commission's findings. Many residents also opposed rezoning to accommodate a new Lowe's Store because they said it would be too big and would require more filling of wetlands than allowed by state law. However, the rezoning passed in 2004 and the store was finally built in 2009. Lowe's then sued the town because they didn't want to pay the required sewer hook up fees. And in 2010, the Massachusetts Department of Environmental Protection found that Lowe's had illegally filled large areas of wetlands on that site and fined the developer more than $15,000.
The World Monuments Fund listed the "Cultural Landscape of Hadley, Massachusetts" on the 2010 World Monuments Watch List of Most Endangered Sites.