Starting in 1921, BSA councils were organized into twelve "regions." According to Patrick Geary in Councils of the BSA, the regions were based on the twelve districts of the Federal Reserve banking system. However, as seen here, these boundaries only loosely resemble each other.
As part of the 1948 integration into the BSA program, the 26 OA areas were abandoned and lodges were redistributed among the twelve scouting regions. Each region was further subdivided into areas, in which lodges participated in annual training conferences.
The Twelve Regions were in operation from 1948-1972. The 1973 New Section Operation created six regions: Northeast, East Central, North Central, Southeast.
Geary, Patrick Councils of the BSA 6th ed. Galveston: n.p., 2000. Print.
Ghizoni, Sandra Kollen. "Reserve Bank Organization Committee Announces Selection of Reserve Bank Cities and District Boundaries." The Sun [New York] Apr. 1914: n. pag. Federal Reserve History. Federal Reserve Bank of Richmond, 23 Nov. 2013. Web. 19 June 2016.
"Map of Local Councils-Boy Scouts of America." Rural Scouting Service, 1957. Rpt. in Order of the Arrow Conclave Handbook. By Frank Dingwerth and Chris Jensen. Vol. 1. 1993. 1-5. Print.
Order of the Arrow National Committee. Area, Area Leaders, and Lodges. 1949. Print.