The Ego in this poem is the one used in common everyday conversation. That is ones sense of self-esteem and self-importance as opposed to the psychoanalytical or metaphysical definitions. While it is healthy and beneficial to have an ego because it leads to confidence and therefore success and other benefits, it is easily inflated. It is this over inflated Ego that is referred to in the poem.
An Ego slain
The procession moves in silent surround,
no wailing lovers to pass,
or weeping kin in black found,
cheeks damp with tears,
for he who lies within.
No robed priest will mumble kind words,
consoling day-trip believers
with thoughts of god.
Only the singing cemetery birds,
lament for he who’s now beneath the sod.
Feel no sadness for me,
this day will not sweet memory stain.
It is a death long sought, to be free,
so welcome this funeral for ego slain.