[3] Europeans first settled in what later became Harvard in the 17th century, along a road connecting Lancaster with Groton that was formally laid out in 1658.

[4] There were few inhabitants until after King Philip's War, in which Groton and Lancaster were attacked and substantially destroyed.

A new town including parts of Lancaster, Groton, and Stow was incorporated in 1732, subject to the proviso that the inhabitants "Settle a learned and Orthodox Minister among them within the space of two years and also erect an House for the publick Worship of God."

One notable early enterprise based in Harvard was the Benjamin Ball Pencil Company,[8] which produced some of the first writing instruments made in the United States.

Despite this and other limited manufacturing, the town economy was primarily based on agriculture until the middle of the 20th century.

One part of town is the site of Harvard Shaker Village, where a utopian religious community was established.

The improving employment opportunities provided by the Industrial Revolution would over the middle decades of the 1800s diminish the attractions of joining the Shaker community.

He and Charles Lane attempted to establish a utopian transcendentalist socialist farm called Fruitlands on the slopes of Prospect Hill in Harvard.

Fruitlands, so called "because the inhabitants hoped to live off the fruits of the land, purchasing nothing from the outside world",[10] saw visits from the likes of Henry David Thoreau and Ralph Waldo Emerson.

[10] Clara Endicott Sears, whose Prospect Hill summer estate, The Pergolas,[11] restored Fruitlands and opened it as a museum in 1914.

[10] Fiske Warren, a follower of Henry George, attempted to establish a single tax zone in Harvard in 1918.

Father Leonard Feeney was a Jesuit priest who held to a literal interpretation of the doctrine "Extra Ecclesiam nulla salus" (or "outside the Church there is no salvation").

Under the direction of Feeney, Catherine Goddard Clarke and others organized into a group called the Slaves of the Immaculate Heart of Mary, an unofficial Catholic entity.

A further split later occurred with some members of the Slaves of the Immaculate Heart of Mary leaving to establish a separate group in New Hampshire.

A branch of the Saint Benedict Center[13] is located in Still River, on the west side of Harvard.

In 1931 Harvard College established the Oak Ridge Observatory at an elevation of 609 feet on Pinnacle Rd, the highest point between Mount Wachusett and the ocean.

In addition to numerous streams and brooks, Bare Hill Pond, a 320-acre lake with its town beach, dock, and several small islands, is a central, iconic locale.

The decline in the population of the town of Harvard from the 1990 census to the 2000 U.S. census is attributable to the 1996 closure of Fort Devens, a U.S. military installation and the departure of military personnel and families residing at Fort Devens, which in large part is within the territory of the town of Harvard.

The Fort Devens property has in large part been converted to civilian use, under the direction of MassDevelopment, a development authority of the Commonwealth of Massachusetts.

In fiscal year 2008, the town of Harvard spent 2.41% ($487,470) of its budget on its public library—approximately $81 per person and since then the library has undergone multiple renovations.