Hereupon means immediately after something happens, or as a direct result of what was just mentioned. It's an old-fashioned word you'll find in classic stories and historical documents rather than everyday conversation.

When a character in an adventure novel discovers a hidden door, the author might write: “She pressed the carved stone, and hereupon the wall began to slide open.” The word signals that one event follows directly from another, like dominoes falling in sequence.

You might see hereupon in older books like Treasure Island or in historical speeches: “The colonists refused to pay the tax, and hereupon the king sent more soldiers.” It connects cause and effect, showing how one action leads straight to the next.

Today, we usually say “then,” “after this,” or “at this point” instead. But hereupon still appears in formal writing and legal documents. Understanding it helps you read classic literature and historical texts more easily. When you spot hereupon in an old book, you know something important is about to happen as a direct consequence of what just occurred.