Creating a comprehensive list of American Army Infantry regiments from 1899 to 2024, along with their online associations and resources, involves a significant amount of detail. Here's a general outline of notable regiments, their historical context, and where you might find more information about them:
Notable Infantry Regiments:
1. 1st Infantry Regiment (The Big Red One)
- Website: [1st Infantry Division Association](http://www.1stinfantry.org/)
2. 2nd Infantry Regiment
- Website: [2nd Infantry Division Association](http://www.2id.org/)
3. 3rd Infantry Regiment (The Old Guard)
- Website: [The Old Guard](https://www.armytimes.com/fort-hood-press-releases/)
4. 4th Infantry Regiment
- Website: [4th Infantry Division Association](http://www.4ida.org/)
5. 5th Infantry Regiment
- Website: [5th Infantry Division Association](http://www.5ida.org/)
6. 6th Infantry Regiment
- Website: [6th Infantry Division Association](http://www.6ida.org/)
7. 7th Infantry Regiment
- Website: [7th Infantry Division Association](http://www.7id.org/)
8. 8th Infantry Regiment
- Website: [8th Infantry Division Association](http://www.8ida.org/)
9. 9th Infantry Regiment
- Website: [9th Infantry Division Association](http://www.9ida.org/)
10. 10th Infantry Regiment
- Website: [10th Mountain Division Association](http://www.10thmountaindivisionassociation.org/)
11. 11th Infantry Regiment
- Website: [11th Infantry Division Association](http://www.11ida.org/)
12. 12th Infantry Regiment
- Website: [12th Infantry Division Association](http://www.12ida.org/)
13. 13th Infantry Regiment
- Website: [13th Infantry Division Association](http://www.13ida.org/)
14. 14th Infantry Regiment
- Website: [14th Infantry Division Association](http://www.14ida.org/)
15. 15th Infantry Regiment
- Website: [15th Infantry Division Association](http://www.15ida.org/)
16. 16th Infantry Regiment
- Website: [16th Infantry Division Association](http://www.16ida.org/)
17. 17th Infantry Regiment
- Website: [17th Infantry Division Association](http://www.17ida.org/)
18. 18th Infantry Regiment
- Website: [18th Infantry Division Association](http://www.18ida.org/)
19. 19th Infantry Regiment
- Website: [19th Infantry Division Association](http://www.19ida.org/)
20. 20th Infantry Regiment
- Website: [20th Infantry Division Association](http://www.20ida.org/)
Online Resources:
- U.S. Army Center of Military History: [Army Historical Resources](https://history.army.mil/)
- The National Archives: [National Archives - Military Records](https://www.archives.gov/research/military)
- American Battlefield Trust: [Battlefield Preservation](https://www.battlefields.org/)
- Military.com: [Regimental Information](https://www.military.com/)
These resources can provide more detailed histories, specific regiment information, and ways to connect with veteran groups and historical associations. For more comprehensive and regiment-specific details, visiting these sites or contacting the relevant association directly would be beneficial.