According to ancient privilege, it is the supreme right of the army, both by law and force of arms, to decide who shall be their king.
10 seconds sound clip from the Alexander the Great (1956) movie soundboard.
You can hear this line at 01:06:23 in the Blu-ray version of the movie.
Quote context
[...]
- May the gods curse the killer from now till evermore, whoever the killer may be.
- Father, neither on my hands nor in my heart. I swear it.
- I hear you wait to declare who is to be your king.
- My father's murder was carefully planned.
- From Demosthenes, the rabble-rouser in Athens, to men here in Pella.
- And there is not world enough nor time enough for these men to escape my vengeance.
[...]