After Victory in Europe Day on May 8, 1945, and Victory over Japan Day on August 14, 1945, World War II was officially over. The 103rd Infantry Division was deactivated on September 22, 1945. The men who fought in the 103rd Infantry Division during World War II memorialized their fallen comrades and continued to remember their service after the war. In 1946, shortly after the de-activation of the 103d Infantry Division (Cactus), an initiative started by Colonel Guy S. Meloy, Jr., former Chief of Staff, began planning for an association.  Colonel Meloy enlisted the assistance of Chief Warrant Officer (CWO) George R. Hackett, Headquarters Company, 103d Infantry Division, to compile a comprehensive roster of former members of the Cactus Division. Colonel Meloy, then a professor of Military Science at Texas A&M University, sponsored the development of an organization for the Association. Major Generals Haffner and McAuliffe would serve as Honorary Presidents, splitting their duties into a half year each. An election of officers was slated for 1947, with elections occurring every year thereafter.

The group was unable to form an official association until 1964. Members of the 3rd Battalion, 409th Infantry Regiment gathered in 1964 and agreed to schedule a meeting in 1965.  After the first successful reunion in 1965, the association held a second reunion in 1966 in Lansing, Michigan. The Association elected Harvey T. Ellsworth (HHC/3rd BN/409th INF/103rd ID) as president. Subsequently, Betty Ellsworth, Harvey's wife, was elected Secretary/Treasurer, and together the couple organized annual reunions. In 1982, at the San Antonio reunion, the association adopted a formal constitution and by-laws. Furthermore, the association agreed to send a yearly delegation to Washington, D.C. to lay a wreath at the Tomb of the Unknown Soldier at Arlington National Cemetery. The association held an annual reunion each year between 1965 and 2017.

As the 103rd Infantry Division Association progressed, various members took initiatives to complete an extensive variety of tasks including the creation of a master list for the division, the organization of annual reunions, the development of memorials in the United States and abroad to remember the accomplishments of the division and those lost, and the even the creation of an annual newsletter which was titled “News from the Cactus Patch”. Association president Mel Wright created the Master Honor Roll of division members who had passed away after the war and organized the list separately by name, by unit and by date of death. Through the exhaustive efforts of the Division Association these veterans and their families were able to gather and enjoy each other’s company and remember those who never got the chance to grow old alongside them.