In Beowulf, how does this long poem convey the somber and mournful mood?

In the epic poem Beowulf, the sombre mournful mood is well
portrayed by the atmospheric description. The keening women filling the air with their
sorrowful crying song, the building of the funeral pyre, the anguish of Beowulf's
beloved fighters at the loss of their adored leader, the depicition of the hilly mounds
in the flatlands all preparing to bid farewell to their champion with heartache in their
souls - all of this helps to build mood and atmosphere in the long poem. Also look in
the rhythm and stresses in the lines, some sound full of grief and longing for something
that is gone and can never come back. The language is full of woe and beating of the
chest at the bereavement of a society.