While history teaches us that instruments were resembling the modern harmonica in older times, and on different continents, the harmonica as we all know it today, comes from the instruments that were invented in the first part of the 19th century, in Vienna.
Here, there were harmonicas available to buy before 1824. A few improvements made the appearance of the modern harmonica possible. A special type of tuning, called Richter tuning, was invented in 1826, and from that point forward, it was adopted universally. The real father of the harmonica is Christian Friedrich Ludwig Buschmann.