Isa 5:26

5:26 signal. This is a signal flag (11:10, 12; 18:3; 49:22; 62:10). Like a commander in battle, the Lord summons the nations to execute His judgment (10:5).

nations afar off. These would be Syria, Assyria, Babylon, etc. The imperial Assyrian army was composed of mercenaries hired from all over the Assyrian Empire.