"3. The second Spanish Rifles started as volunteer militia unit but was eventually considered a local defense formation because it had Spanish speaking nationals who were not citizens of Louisiana."

I am a little confused by this statement of yours, which makes me think that the lady doing the research would be very much more perplexed. You state that it started as a volunteer militia unit but was eventually considered a local defense formation. It seems to me that you are repeating the same thing using different words.