How long has storytelling existed?

Effective (alphabetic) writing was invented by the Phoenicians in the 9th Century BCE, and its symbols were adapted by other cultures, notably Greek. The earliest extant historian was Herodotus of Halicarnassos who wrote his Histories (= researches) in the 430s BCE. Other scripts were used earlier for commercial, religious, and official records eg Egyptian, Sumerian, Mycenaean, Assyrian, Hebrew, but what we think of today as history, ie a coherent account of the changes in human affairs, begins with Herodotus and his mostly lost contemporaries.