An elegy is a sad poem usually written for funerals so i would go with the first one
I believe the phrase unexplained glory meant <span>"the glory of fighting and dying in battle."
The glory is considered as 'unexplained' because of pf the questionable method on how we get the glory. In war period, we obtain this glory by killing others and bring misery for those that left by the deceased.</span>
I hope this helps honestly