Hi, you're fully right, American Eagle isn't well documented at all. I do have only limited information, but I'm happy to help.
First of all, are you sure that your Bike is an early 90s build?
American Eagle was introduced by the Dutch company Veltec-Rentmeeste in 1993.
The road cycling brand Concorde was used as co-brand to didn't start as unknown.
A bit of history is on their current webpage
The CST Sandd American Eagle Mountain Bike Racing Team is a UCI Elite Mountainbike Trade Team, Number 1 of the world! Managed by Bart Brentjens
americaneagle.online
in the "our history" "read more" section, but be carefully it's a lot of marketing blahblah, California, blahblah...
The first American Eagle Bikes, at least the ones introduced in Germany, had been 1994, at this time all models had been called "Stratos" just with a different number at the end, from 403 to 703.
Later line ups had names like Durango, Vail or Big Bear had been introduced and the race team has been sponsored.
Here's an Ad from 1995 with model portfolio
and spec sheet
and picture from the race team
From what i do know, they didn't miss any opportunity to leave an "american" bike style impression, but this was all just fake to polish the image.
The company was led out of the Netherlands and Bikes had been produced in Taiwan.
Bart Brentjens Atlanta winning bike 1996 was BTW build by Markus Storck.