The name “Peerless” — a Keene-based brand in the insurance industry for more than a century —is being shelved by Boston-based owner Liberty Mutual.

The scheduled disappearance of the Peerless Insurance Co. name in favor of the parent’s brand is yet to fully register. Some policy holders, for example, might not see the difference until 2014.

But a corporate restructuring that’s associated with the name change is well under way, one aim being to give a tighter focus to Peerless and some other Liberty Mutual insurance units that for years provided multiple lines of personal and commercial insurance in many states; the new target is commercial insurance to businesses with fewer than 1,000 employees — in Peerless’s case in New England, New York and New Jersey.

Liberty Mutual officials suggest the general public in Keene won’t notice much, if any, change.

“We anticipate staffing to be fairly level there,” a Liberty Mutual spokesman said this week.

Peerless, which wrote about $900 million in commercial lines premiums in 2011, accounts for about one-quarter of Liberty Mutual’s 450-member workforce on Maple Avenue in Keene. The remaining staff is deployed to related Liberty Mutual operations, including Safeco — a personal home and auto insurer Liberty Mutual bought in 2008 that’s headquartered in Seattle.

Indeed, it was Liberty Mutual’s $6.2 billion purchase of Safeco that helped set in motion a concentration of eight Liberty Mutual regional companies, including Peerless, in commercial insurance, leaving all personal lines to Safeco.

Under the rebranding, the Keene operations will take on the name of Liberty Mutual Insurance. That’s the short form. The long form is Northeast Region for Business Insurance at Liberty Mutual.

The impact on the market will show up initially through the company’s distribution network of 1,600 independent agents in New England, New York and New Jersey, where about 220,000 policies are in force.

Thomas J. Minkler, president of Clark-Mortenson Agency in Keene, one of those agents, said when he recently heard of the rebranding of the longtime Keene business his immediate reaction was “a bit melancholy.”

But he said he was heartened by two things — first, that the Liberty Mutual name is more readily recognizable in the broad marketplace than Peerless, and second, that Liberty Mutual appears to be giving managers of what he described as “the new Peerless” more autonomy than what traditionally results from business consolidations directed from elsewhere.

“Our hope is that they have the same high-quality people out there,” Minkler said. “I haven’t seen any slipping.”

Other close observers of the change are in the local charitable sector — people who are naturally sensitive to any move by distant corporate managers that might dilute local allegiances.

Kathy Harrington, who heads the Monadnock United Way, says she would like to see a continuation of what she termed “the Peerless culture,” which she characterized as taking a strong interest in community affairs.

Her preference is based on experience; traditionally, outside acquisitions or consolidations of local companies can lead to cutbacks in executive participation in local charitable affairs, and also to reductions in employee support of local fund-raising campaigns in favor of other projects that have a corporate parent’s blessing.

Of what she has seen so far, she said, “There is still a complete and full commitment of the Peerless culture.”

In an interview, Michael R. Christiansen, Peerless’s president and chief executive, said the company “is a strong supporter of local causes and charities. There will be no change there.”

Among other things, the company is a co-sponsor of the 2012-13 season at the Redfern Arts Center on Brickyard Pond at Keene State College. It’s also a supporter of the Clarence DeMar Marathon, among other local events.

In Peerless’ long sweep of history, the rebranding hardly represents the first change in direction and ownership.

Rooted in a Keene-based insurance agency that was started in 1893, the company was incorporated in 1901 as Peerless Casualty Co. to sell accident and health insurance, according to Upper Ashuelot, the history of Keene.

In 1957, a Dutch firm seeking a U.S. presence bought into the company, by then owned by a group of New England insurers. The Dutch firm, De Nederlanden, eventually bought full control, after which it went on an acquisition binge in the U.S., scooping up regional insurers in other parts of the country and generally directing them from the Peerless headquarters in Keene.

Ultimately, concerned that it wouldn’t be able to develop a large enough share of the U.S. property and casualty market to make a difference, in 1998 the Dutch firm sold its casualty insurers to the British-owned Guardian Royal Exchange, which the following year sold them to Liberty Mutual, now one of the largest insurers in the United States.

At the time of the sale to Liberty Mutual, Christiansen was a regional vice president for Peerless in Syracuse, N.Y.; he was named president in Keene the following year, and later held other insurance industry positions before returning to head Peerless again in 2007.

In something of an anomaly for a small New England city, Keene hosts another longtime insurer that has also undergone change, including a shift of headquarters out of town.

The National Grange Mutual Insurance Co. was founded in 1923 in Keene to provide insurance to Grange fraternity members.

Today it’s the largest of nine insurance companies owned by Main Street America Group, which was formed about the time the executive offices of NGM moved from Keene to Jacksonville, Fla., 10 years ago.

Main Street America, a commercial and personal casualty insurance firm with projected 2012 premiums of $970 million, formally describes Keene-based NGM, which has offices on West Street, as its flagship carrier.