"...iron civilization conquered the Bronze Age civilization..."
I am unaware of any evidence of this anywhere. Prior to Iron Age technology, all Bronze Age civilizations had already collapsed. Once the climactic disruption caused by the grand solar minimum had ended, societies again began increasing in complexity and population, and the discovery of iron smelting and ubiquitous presence of iron ores globally made bronze technology obsolete.
In almost no cases did Iron Age technology face Bronze Age technology I am aware of.