Fort Mackinac is located on Mackinac Island, Michigan, in the narrow waterway between Lakes Huron and Michigan, very near the present border with Canada. During more than a century as an active military post, the fort changed ownership several times and participated directly in only one conflict, the War of 1812. British soldiers built this outpost in 1781, on a high limestone bluff overlooking the Straits of Mackinac. The isolated post provided much needed protection and support for the Great Lakes fur trade. In 1783, following the American victory in the Revolutionary War, the fort became United States property. However, the British remained for another 13 years in an attempt to control fur trade in the upper Great Lakes. In 1796 they evacuated the fort in accordance with the terms of Jay’s Treaty, and the American army occupied and repaired the aging outpost. When the United States declared war on Great Britain in June 1812, the British attacked and recaptured the fort, holding it until the Treaty of Ghent ended the war and returned the post to American possession. The fort sat idle during the Civil War and thereafter was irregularly garrisoned by troops until 1895, when it was finally closed.
The painting successfully conveys a place and climate quite different from the other locations in the fort series. Like a walled town, the elevated structure consists of separate buildings within the walls. At the right, outside the fort, is a very large house. At the foot of the steep hill are three houses, then a stone wall with a gate, and finally the shore with a rudimentary jetty. A canoe approaches the jetty. A large fishing boat is on the shore, partly covered, with a fisherman in attendance. The looming cloud in the darkening sky warns of an approaching storm, whose advance winds have stirred the water of this safe harbor into small whitecaps, occasioning this small flurry of activity. In the distance at the left, beyond the point, the viewer glimpses a steamship and a sail on Lake Michigan. For the weather-bearing clouds, Seth Eastman has employed blended swirls of blue-black paint in an improvisatory pattern. It is clear from the painting that the island is populated, if sparsely, but there is no evidence of the very slight military presence that was still there in 1872.
During the late 18th century and through much of the 19th century, army forts were constructed throughout the United States to defend the growing nation from a variety of threats, both perceived and real. Seventeen of these sites are depicted in a collection painted especially for the U.S. Capitol by Seth Eastman. Born in 1808 in Brunswick, Maine, Eastman found expression for his artistic skills in a military career. After graduating from the U.S. Military Academy at West Point, where officers-in-training were taught basic drawing and drafting techniques, Eastman was posted to forts in Wisconsin and Minnesota before returning to West Point as assistant teacher of drawing. Eastman also established himself as an accomplished landscape painter, and between 1836 and 1840, 17 of his oils were exhibited at the National Academy of Design in New York City. His election as an honorary member of the academy in 1838 further enhanced his status as an artist.
Transferred to posts in Florida, Minnesota, and Texas in the 1840s, Eastman became interesed in the Native Americans of these regions and made numerous sketches of the people and their customs. This experience prepared him for the next five yeas in Washington, D.C., where he was assigned to the commissioner of Indian Affairs and illustrated Henry Rowe Schoolcraft's important six-volume Historical and Statistical Information Respecting the History, Condition, and Prospects of the Indian Tribes of the United States. During this time Eastman also assisted Captain Montgomery C. Meigs, superintendent of the Capitol extension, in securing the services of several Native Americans to model for the sculptors working on the 1850s addition to the building.
In 1867 Eastman returned to the Capitol, this time to paint a series of nine scenes of Native American life for the House Committee on Indian Affairs. Eastman's talent and his special knowledge of the subject certainly qualified him for the commission, which was obtained for him by House Ways and Means Committee Chairman Robert C. Schenck of Ohio. Schenck, a former Civil War officer who, like Eastman, was retired for disability during the war, believed American–-not European–-artists should recieve the Capitol commissions. In introducing a resolution urging the hiring of Eastman for the project, Schenck remarked:
We have been paying for decorations, some displaying good taste and others of tawdry character, a great deal of money to Italian artists and others, while we have American talent much more competent for the work. Among others . . . is General Eastman, who . . . is more of an artist in all that relates to the Indians, except possibly Catlin and Stanley, than any we have had in this country. . . . If assigned to this duty General Eastman will draw his full pay as lieutenant colonel, instead of as on the retired list, making a difference of about $1,200 or $1,500 a year. For at the most $1,500 a year we will secure service for which we have been paying tens of thousands of dollars to foreign artists, and we will get better work done. 
Schenck's resolution was approved by the House but tabled by the Senate. Nevertheless, the retired Eastman was placed–-by special order of the War Department–-on "active duty" so that he could be compensated for creating works of art for the Capitol. He finished the nine paintings in 1869.
In 1870 House Military Affairs Committee Chairman John A. Logan of Illinois proposed that Eastman produce 17 canvases depicting army forts. It is indicative of the post-Civil War sentiment in America that Logan specified that Eastman was not to paint battle scenes; indeed, the mood of these forts set in landscapes is serene, even nostalgic to some degree. Never a well man, Eastman was aged and ailing by the time he received the commission, and it is not known if he visited the forts. He had been stationed at several of these during his military career, and as a trained topographical draftsman he probably had plans, elevations, and even photographs of the forts at his disposal. Eastman completed the series between 1870 and 1875.
Charles E. Fairman, longtime curator of the Capitol, was slightly dismissive of Eastman's fort paintings. He thought they were "probably more valuable as examples of historical accuracy . . . than for purely decorative purposes."  He explained that it was important that knowledge concerning government fortifications should be easily accessible and these pictures "contain desired information and also relieve acceptably what might otherwise be blank spaces upon an uninteresting wall."  Yet without touting Eastman's paintings as masterpieces, it is still possible to value them as considerably more than repositories of "desired information."
For many years, the fort paintings hung in the House Military Affairs Committee Room, first in the Capitol and later in the Cannon House Office Building. During the late 1930s, they were returned to the Capitol for public display. Of the 17 paintings, eight are located in the Senate, while the others are displayed on the House side of the Capitol. Eastman was working on the West Point painting when he died in 1875.
1. Congressional Globe (26 March 1867) 40th Cong., 1st sess.: 362.
2. Charles E. Fairman, Art and Artists of the Capitol of the United States of America (Washington, D.C.: Government Printing Office, 1927), 239