Over the last century or so, several theories have arisen on the origin of the runes, each having a strong body of supporters at different times. The nineteenth-century Danish rune scholar L. F. A. WimmerM, struck by the obvious similarity between certain runes and Latin letters, put forward the notion that a single German scribe, using the Latin alphabet as a guide, created the runic alphabet around the time of Christ for the purpose of written communication. This has historic parallels - Wulfila created the Gothic alphabet for the West Goths in the fourth century. The idea that the runes were invented by one man was quite popular among academics because it eliminated so many difficult questions as to how and why runes came into being.
Another popular theory, put forward by the Scandinavian scholar Friesen around 1900, says that Gothic merchants created the runes in the third century on the shores of the Black Sea for the purpose of trade, taking as their model the Greek alphabet with some admixture of the Latin. This gained many supporters in English-speaking nations because it was included in the influential Encyclopaedia Britannica, 1929 edition.
In the 1930s, when the nationalist fervor of Nazi Germany reached it's fanatical peak, German scholars attempted to prove that runes were purely Aryan in origin, and that they owed nothing to the alphabets of Greece and Rome. Additionally, they claimed that all alphabets around the world were born from the stone-age prototypes of the runes. These theories were inspired by the mystical writings of Guido von List and Friedrich Bernhard Marby in the nineteenth century. After World War II, these ideas were generally ridiculed.
The theory that is now put forward most often to explain the birth of runes says that a tribe of German mercenaries crossed the Alps into northern Italy in the fourth century B.C., where they practiced their martial trade for some generations. They would have carried a knowledge of the primitive magical symbols used by their shamans with them. In their new land, a fusion took place between the magic symbols and their meanings and the letters of the Etruscan alphabet, then in use in northern Italy. Around the second century B.C., knowledge of runes passed back over the Alps and was disseminated through Germany by the Cimbri tribe. At some time in their early development, perhaps around the time they began to be used for writing, the runes must have been strongly influenced by the Latin alphabet, as the similarity between some runes and Latin letters is too obvious to be denied.
A few academics go so far as to deny that runes ever had a significant occult function. But it is generally agreed that in the early centuries of their use they were primarily magical tools, and remained strongly linked to magic throughout their history. Only in their decadence did their use solely as a script for recording information become widespread. Even then, runes were never the main instrument of written communication. They were inscribed on stone monuments, weapons, and other artifacts, and placed in burial mounds, precisely because they were magical. The magical associations of runes lent authority to any message written with them. It was the voice of the gods speaking to the reader - a holy script, even as Latin was until recent years the sacred language of the Catholic Church.
Once their usefulness as instruments of magic became known to the Teutonic tribes, runes spread like wildfire across northern Europe. One tribe called the Heruli specialized in rune magic, so much so that long after the tribe itself ceased to exist Herulian was a byword for rune master. The runes were carried by the Saxons to England, and they spread into Scandinavia, and from there to Iceland.
The Vikings took the runes on their world-spanning voyages and left runes as graffiti in many unexpected corners of the ancient world. Runes have been discovered in such diverse places as Piraeus in Greece, Berezanji on the Black Sea, Ireland, Scotland, the Hebrides, the Isle of Man, and Baffin Bay in Greenland. There has even been speculation that the Vikings left runes in Nova Scotia and Minnesota, but no credible evidence has been found to support either of these claims.
Runes survived longer in Scandinavia, and longest of all in Iceland - not because these lands were especially fond of them but because they resisted most strongly the attempts of the Church to suppress pagan religions and customs. This is the only reason that runes, and the northern gods themselves for that matter, are identified with Scandinavia. Runes are a German invention. They reached their greatest refinement as a magical system with the German futhark (a word coined from the first six German runes) in the eighth century, after which they began to be adapted to suit regional language requirements and lost some of the clarity of their structure.
The death of the runes as magical instruments can be fixed historically at 1639, when they were explicitly banned by the official laws of Iceland. Those found with runes in their possession were burned alive. By this date they had long since ceased to be anything but a curiosity in the rest of the world, where reference to them would have elicited the same blank stare that it does from the average person today. It is fortunate that a few passing references were made about rune use in the Icelandic sagas, and in some Old English poems. Otherwise, we would know nothing about them and would not have enough information to understand runes.