It was born as the main competition for US clubs.
During the years many attempts were made to create professional or semi professional leagues, nation wide like Rugby Super League and Pro Rugby or regional like Pacific Rugby Premiership, American Rugby Premiership and California Cup.
For this reason the main clubs did not always take part to the championship or they played with the 2nd XVs.
Since 2013/14 USA Rugby is geographically divided into 8 regions:
- Atlantic North, including Connecticut, Maine, Massachussets, New Hampshier, northern New Jersey, New York, Rhode Island and Vermont.
- Mid Atlantic, including D.C., Deleware, Maryland, southern New Jersey, Pennsylvania, Virginia and West Virginia.
- Midwest, including Illinois, Indiana, Iowa, Kentucky, Michigan, Minnesota, Ohio and Wisconsin.
- South, including Alabama, Carolinas, Florida, Georgia, southern Louisiana, Mississipi and Tennessee. In these years there are no D1 teams from this region.
- Frontier, including Colorado, Kansas, Missouri, Nebraska, South Dakota, Utah and Wyoming. In these years there are no D1 teams from this region.
- Red River, including Arkansas, northern Louisiana, Oklahoma and Texas.
- Pacific Coast, including northern California, Idaho, Montana, Nevada, Oregon and Washington.
- Southern California, including Arizona, southern California and New Mexico.
www.usarugby.org - USA federation official site.
fr.wikipedia.org/wiki/Championnat_des_Etats-Unis_de_rugby_à_XV - Wikipedia pages about DI Championship
www.macrugby.org - Mid-Atlantic conference official site
www.marfu.org - Mid-Atlantic union official site
www.nerfu.org - New England union official site
www.midwestrugby.org - Midwest union official site (abandoned)
www.wrfu.org - Western union official site (abandoned)
www.texasrugbyunion.org - Texas union official site
www.rockymountainrugby.org - Rocky Mountains union official site
www.scrfu.org - Southern California union official site
www.ncrfu.org - Northern California union official site
pnrfu.com - Pacific North union official site
pacificcoastrugby.com - Pacific Coast union official site (abandoned)
The site usarugbysouth.com, no longer existing, was scanned using web.archive.org
Also the above sites were scanned using web.archive.org