| 1866 | The General Congregational Conference of Minnesota, meeting in Faribault in October, votes to prepare articles of incorporation for a college in Northfield. It is chartered formally in December, bringing to fruition years of efforts by Charles M. Goodsell and others. |
| 1867 | American House is purchased as the first home of "Northfield College." (Renamed Carleton College in 1871.) The college sells it 1887. |
| 1869 | The cornerstone is laid for the first permanent building (future Willis Hall) on land deeded to “Northfield College” by Northfielders Charles M. Goodsell and Charles A. Wheaton. This building, as well as the entire Carleton campus and the city of Northfield, is situated within the historic lands of the indigenous Dakota people. |
| 1870 | Rev. James W. Strong, a Beloit College graduate serving as pastor to the Congregational church in Faribault, accepts an invitation to become the College's first president. |
| 1870 | The "collegiate department" opens in September with a class of four freshmen. |
| 1870 | President Strong travels to New England on a fundraising mission for the College. In December, following a visit with William Carleton of Charlestown, Mass., Strong is seriously injured in a railway accident. |
| 1871 | Reportedly impressed by the almost miraculous survival of Dr. Strong, William Carleton ensures the College's survival with a $50,000 gift. An appreciative board of trustees renames the College in his honor. |
| 1872 | The College's first building is completed. It was named Willis Hall the following year in honor of Susan Willis Carleton. |
| 1873 | The Philomathian Society is the first of many student "literary societies" organized on campus. |
| 1874 | James J. Dow and Myra A. Brown are the first two students awarded bachelor's degrees, giving commencement orations, respectively, on "The Attainment of True Manhood" and "The Intellectual Culture of Women." Six months later, on Christmas Day, they marry. |
| 1876 | Death of William Carleton and Susan Willis Carleton. Joseph Lee Heywood, College treasurer, is murdered in the Jesse James Gang's raid on the First National Bank of Northfield. |
| 1877 | First edition of the Carletonian is issued by Philomathian Society |
| 1878 | The first Carleton Observatory is built. (Razed in 1905 to make way for Laird Hall.) |
| 1878 | Inauguration of the Observatory's telegraph time service, which eventually sets time for over 12,000 miles of railroad across the Northwest. |
| 1879 | The original Willis Hall destroyed by fire in December. It is rebuilt the following year. |
| 1880 | A Science Building erected - it is named Williams Hall in 1883. |
| 1880 | "Seccombe House," then west of the present Chapel, is in use as a music hall, 1880-1914. |
| 1881 | The Carleton Alumni Association is formed. |
| 1881 | Ladies Hall, a dormitory for women is built. It is occupied in January 1883 and renamed Gridley Hall in 1886. |
| 1882 | Faculty bans "mixed" literary societies. |
| 1882 | William Wallace Payne, director of the Carleton observatory, begins publication of the world's only popular astronomical journal, The Sidereal Messenger. Later he also founded Popular Astronomy, a Carleton-issued publication destined to be the best-known journal in the field for half a century. |
| 1885 | Harlan W. Page is appointed financial secretary, the College's first salaried officer not also a member of the faculty. |
| 1886 | Willis Bell chimes are donated by Robbins Battell. |
| 1887 | The New Observatory opens; it is named for Charles M. Goodsell in 1891. |
| 1887 | The Library moves from Williams Hall to the Old Observatory. |
| 1887 | Probable date of Carleton's first formal intercollegiate athletic contest: a Carleton baseball teams beats a St. Olaf nine in May. June brings the first of a long series of annual spring "Field Days" which feature a variety of athletic competitions. |
| 1889 | First Algol was published. |
| 1889 | Maize is chosen as the school color. |
| 1890 | Limited electives are introduced for juniors and seniors. |
| 1891 | Tsune Watanabe, of Japan, graduates. She is Carleton's first nonwestern student. |
| 1891 | Basketball is invented by James A. Naismith. His roommate at YMCA Training College in Springfield, Mass., is Max Exner, who comes to Carleton the following year, bringing the game with him. |
| 1891 | The "preparatory department" is severed from the College and begins independent existence as the Carleton Academy. |
