Kappa Alpha Theta was the first national Greek letter fraternity for women, founded January 27, 1870, at Indiana Asbury (now DePauw) University in Greencastle, Indiana. When the Alpha Beta Chapter was established at Swarthmore College on September 24, 1891, it was the first women's fraternity on campus. It maintained a steady presence there until the abolishment of women's fraternities on December 12, 1933.

At the time that the Swarthmore chapter was installed, the fraternity had twenty-one chapters throughout the country. Its establishment at Swarthmore came about as the result of the efforts of two distinct student organizations, working separately. One was a group of mostly senior women which called itself Phi Delta Pi. Its members wore a badge with a representation of a penny cut in half, polished on one side, and engraved with the Greek letters. The other organization was composed of women from the three lower classes. One of this group's customs involved a confessional box. At weekly meetings, each member would place notes detailing their grievances toward other members in the box. Then, these faults [were] frankly and solemnly discussed for the sake of improvement of the group. Both groups approached the Dean of Women with their desire to establish a women's fraternity at Swarthmore. It was she who suggested that the women unite in application for a Kappa Alpha Theta charter.

Following approval, the chapter initiation was held at the home of Annie (Class of 1892) and Helen (1894) Hillborn, who lived near the College campus, on September 24, 1891. The other charter members were: Hannah Clothier, 1891; Dora Lewis, 1891; M. Ellen Atkinson, 1892; Ellen Pyle, 1892; Anna S. Atkinson, ex-1893; Jane Atkinson, 1893; and Ellen Williams, 1893. Many of them had sisters or cousins in the Iota Chapter of Cornell University, which oversaw the ceremony. A branch of the Theta alumnae organization was established in Philadelphia in 1898 and had 57 members by 1928. The Swarthmore Chapter edited the national Kappa Alpha Theta journal from 1903-1905 and hosted the fraternity's national convention in 1905.

The campus buildings now known simply as the six Lodges were completed in 1928 with the original function of serving as women's fraternity lodges, an annex of sorts to the women's residential area in Worth Hall. Kappa Alpha Theta used the sixth lodge, the one nearest to the Benjamin West house. The other women's fraternities at the time were assigned to the other five lodges in order of their establishment after Kappa Alpha Theta at the college, with the most recently installed fraternity in lodge 1: Delta Gamma (#1), Phi Mu (#2), Chi Omega (#3), Pi Beta Phi (#4), and Kappa Gamma (#5). The lodges consisted of living-rooms, kitchenette, and a guest suite and did not serve as regular living quarters for fraternity members. By 1932, there were 41 Thetas on campus. This membership was exceeded in size only by the 42 women of Pi Beta Phi, a sorority installed on campus in 1892.

The construction of the Bond Memorial Hall and Women's Lodges was quickly followed, however, by the dissolution of all women's fraternities at the College. The role of Greek life on campus had been the subject of debate for years. In 1931 an inquiry was suggested to President Aydelotte by a group of graduates who were members of fraternities and wanted to see the social atmosphere on campus improve. Aydelotte, in response, published a statement in the November 24, 1931, issue of The Phoenix, the College newspaper, outlining his concerns about the centrality of fraternities to social life on campus. It was the second time in ten years that the abolishment of women's fraternities was proposed. The President pointed out that fraternity membership among female students increased sharply from 60% of the female population upon his arrival at the College in 1920 to 77% in 1931. He seems to have echoed the feelings of many when he voiced concern that hasty rushing at the beginning of freshman year inevitably produces artificial social groups that segmented the student body and undermined the college's sense of community. Exclusion from fraternity life could amount, in the words of one Class of 1911 alumna, to the tortures of being walled up in that little college in badge less social ostracism. President Aydelotte was hopeful that the college's social shortcomings could be resolved by reform of the fraternity system but he made it clear that if such changes were not effected by the fraternities, then they would be laid down. A series of College-wide referenda of the female population resulted in indecision, as various measures for social reform were proposed and sometimes attempted. The issue was finally laid to rest on December 12, 1933, when women students voted decisively for the abolishment of the fraternities.

Despite its demise in 1933, the Swarthmore Chapter of Kappa Alpha Theta did leave a legacy which attracted attention from the national press. This was the so-called Round Robin Letter which was sent yearly between 14 Thetas from the classes of 1909-1911 until the death of the final alumna in 1980. It was a way for the former sisters to keep in touch, each of them replacing her letter from the previous year with a new one filled with the latest account of her activities. The correspondents held a reunion in 1950, and by 1954 the round robin letter was believed to be the oldest missive of its kind in the world.