The MAA was established in 1915. But the roots of the Association can be traced to the 1894 founding of the American Mathematical Monthly by Benjamin Finkel, who wrote "Most of our existing journals deal almost exclusively with subjects beyond the reach of the average student or teacher of mathematics or at least with subjects with which they are familiar, and little, if any, space, is devoted to the solution of problems…No pains will be spared on the part of the Editors to make this the most interesting and most popular journal published in America."
While the Monthly was valued by many in the mathematical community, especially those concerned with teaching, within two decades it became clear that it could not thrive without organizational structure and support. An effort was made to have the American Mathematical Society (AMS) provide that home, but, after a study of that possibility in early 1914, the Council of the AMS adopted the following resolution:
It is deemed unwise for the American Mathematical Society to enter into the activities of the special field now covered by the American Mathematical Monthly; but the Council desires to express its realization of the importance of the work in this field and its value to mathematical science, and to say that should an organization be formed to deal specifically with this work, the Society would entertain toward such an organization only feelings of hearty good will and encouragement.
After an informal effort by a self-organized group of mathematics faculty to generate sufficient interest, E. R. Hedrick of the University of Missouri presided over a meeting on December 30-31, 1915, and was subsequently elected as the first president of the newly-minted Mathematical Association of America.
Collaboration between AMS and MAA has been strong throughout the last century, and is perhaps best reflected by the organizations' shared responsibility for the annual Joint Mathematics Meetings.
The good will among the broader mathematical sciences community is reflected in the MAA's participation in the Joint Policy Board for Mathematics, and the Conference Board of the Mathematical Sciences.
Over our first century, MAA has certainly grown, but continues to maintain our leadership in all aspects of the undergraduate program in mathematics.
For in-depth historical information on the early years of the Association, see The Mathematical Association of America: Its First Fifty Years.
In 1976, the MAA published The Bicentennial Tribute to American Mathematics: 1776-1976.
You can also learn more about the history of the MAA Committee on the Undergraduate Program in Mathematics.