At Lomekwi 3 in Kenya, researchers unearthed knapped stones about 3.3 million years old, more than 500,000 years before the earliest fossils assigned to the genus Homo. So toolmaking wasn't invented by 'humans' in the strict sense: other hominins already knew how to strike stone to get a sharp edge.
Around 2300 BCE, Enheduanna, daughter of King Sargon of Akkad, became high priestess of the Moon god at Ur. She composed hymns to the goddess Inanna and put her name to them. She is the oldest person identified as the author of a literary work, about 1,500 years before Homer.
Squeeze Earth's 4.5 billion years into a single 24-hour day. Homo sapiens shows up around 11:59:54 p.m., roughly six seconds before midnight. All of written history, from Sumerian tablets to today, fits into the final tenth of a second. A cosmic blink.