China has a long history as one of the oldest civilizations in the world, with written records dating back 4,000 years. It developed from early agricultural societies along the Yellow River into a unified nation under the Yellow Emperor and Fiery Emperor around 5,000 years ago. This early Chinese civilization advanced technologies like pottery, sericulture, and bronze working. From the Xia Dynasty 4,000 years ago through the 19th century, China experienced a long period of imperial rule and was a global leader in many fields of science and innovation until the Middle Ages. Today, China continues to modernize while also drawing on its rich ancient cultural traditions.