The ancient Greeks fought two famous battles against the army of the Persian Empire in the early era of bronze between the early and late 400s BC. These were the battles of Thermopylae and Marathon. And these battles, along with the Greek invention of bronze weapons and armor, allowed the Greek civilizations to weather the storm that was the invasion of the Persian Empire.
An example of a Greek bronze short sword.
Greek bronze helm, C. 600 BC.
The advantage bronze provided to the Greeks allowed a small number of Spartan hoplites to stand and inflict outrageous casualties on a much larger Persian host at a pass known as Thermopylae with cliffs to their left and a fall into the ocean to their right. Although they were later surrounded and killed down to the last man, this battle lasted much longer than it would be expected for 300 men to stand against hundreds of thousands.
Metal armor made the difference by making many of the Persian weapons nearly useless against the hoplites. When the Persians advanced to the Greek line, the contest between each Greek with the Persian advancing toward him was greatly weighted in favor of the Greek. This is because of a few different factors like extensive training and discipline, but perhaps the greatest advantage was the disparity in their equipment. Persians were armed with much cruder weapons and wore cloth and leather armors. These were not adequate to the task of stopping sharp bronze swords, whereas the whips some of the Persians are said to have carried would be totally useless against bronze armor.
Because the Greeks had these advantages during the Greco-Persian wars, their civilizations survived to influence the western civilizations around the Mediterranean. In some ways the development of bronze working technology was the basis for the ancient Greek say in how things are today.