The Moose was founded by Dr. John Henry Wilson and a group of his friends in 1888 in Louisville, Kentucky, as a social club. While it remains essentially an American club, it changed its name to Moose International in 1991 with memberships emanating throughout the United States, Canada, Great Britain, and Bermuda. The basic unit is the Lodge, which follows the pattern established by Masons: the Moose have club room or rooms, plus a Lodge room with an altar. The Moose confer an initiatory degree, and after six month membership, the member becomes eligible for the second degree, Legion of the Moose. A third degree of Fellowship Degree is awarded for service to the fraternity. The fourth and highest degree, that of Pilgrim, is honorific and is awarded to few Moose. The Moose make community service a strong component of their activities.

Moose International headquarters is approximately 38 miles west of Chicago at Mooseheart, Illinois. Men's Lodges and the Ladies Chapters across the fraternity contribute to Moose-sponsored programs such as Mooseheart, the 1,200-acre Illinois home and school for children in need. Moosehaven, a retirement home for Moose and their wives, was founded in 1922 on the banks of the St. John's River at Orange Park, 14 miles south of Jacksonville, Florida. There are more than 30 buildings on about 60 acres of land, with more than a third of a mile of river frontage. "Every resident whose physical condition will permit is assigned to some daily duty usually not to exceed three hours," and everyone receives a monthly allowance. Those no longer able to work are called "Sunshiners." Their job is to sit in rocking chairs in the sun, and smile at passers-by. There is a well-equipped 150 bed hospital, in addition to many other facilities.

Aside from Mooseheart and Moosehaven, Moose Lodges also support a number of health oriented charities, such as the March of Dimes, Muscular Dystrophy, Heart Fund, Cancer Crusade, Cerebral Palsy, and much more. Many Lodges are also active in highway safety, Boys and Girls Scouting, civil defense cooperation and local community activities of all kinds.

With over 2,100 locations and more than 1.7 million members, Moose Lodges and Family Centers, on the other hand, provide affordable activities for members and their families. From sporting events and family dinners, to holiday parties, teen dances and everyday social activities, local Moose Lodges provide a sense of camaraderie and fellowship which can only be defined as second to none.