I've read the Fallout: Equestria and Fallout: Equestria Project Horizons and I love them. I'm a big fan of them, but I like to read what happens before the war. How the war started. What the mane 6 did before and during the great war.
I've looked around the Fallout: Equestria expanded universe for any story dating back to the great war, but couldn't find any. If anypony knows of any Fo:E that starts at the beginning of the great war, please let me know. I love to read it.
Thanks,
Dash2600

5075379
How about the middle of the Great War?

From what I can tell, the very beginning didn't have much going on. Like, during the height of the gems-for-coal trade agreement or something?

5075379 May check out Origin Story by Kkat. Probably the closest you'll find to a pre-war story.

5075404
Damn, beat me to it

5075379
What Sober said. All sidefics are, after all, sidefics; even those that play during the war rarely focus on the mane 6. That was already in the main story, after all; we know what they did.

I did write a story that has rather frequent flashbacks to the war times, and even includes the occasional Pinkie Pie
(also, diamond dogs )

I actually just today read a story called Littlehorn that tries to tell the story of said tragedy from an internal POV. That's pre-war!

Actually want to do a "All quiet on the Equestrian front" from the POV for a zebra legionnaire, from his recruitment at start of tensions with Equestria to the outbreak of war at the Wonder bolts/pirate island incident (Battle of the Somme), to the sieges of Hoofington (Battle of Kursk), to the attack on Shattered Hoof Ridge facility (Omaha beach), the attempted assassinations of ministry mares (july plot), death of Big Macintosh (bay of pigs), right up till the end of the world as both sides escalate to the apocalypse.

Basically 20th century conflict ponified and reshaped into Fallout Equestrian where the Cuban missile crisis ended a little differently.

My story "A Robot's Lament" starts at the end of the Great War, and will soon have a lot of flashbacks. It could be a good starting point.