There is only one major accomplishment that took place during the 1500 year long classical period. This is the formation of large successful civilations. These large civilations were in China, India, the Mediteraniean, and the Middle East. they acheived this by uniting states, tribes, and nomadic groups. Silk was traded from East Asia to the Mediteranean, but other than that, there wasn't much communication or trade between empires. Sometimes civilations would attempt to conquer other civilations, such as Alexander the great. This caused two cultures coming directly together. The classical period started around 1000 bce probably because of the discovery of iron, which could be used to make stronger tools and weapons. Classical civilations were much more powerful than the civilations preceding them. They were larger in size, had better economies, and more political power. Because communication was hard and direct contact was rare, each civilation had it's own socail structure, religion political system, sience and art. Although the classical period only really applied to china, india, the mediteranean, and the middle east, their civilations affected the entire world. The Greeks made scientific breakthroughs that were later built on by other civilations. They also traded with parts of Africa. india traded with many parts of the world, extending all the way to Southeast Asia. All of the Classical civilations developed in art, politics, and philosophy.