Cuneiform is one of the earliest known forms of written expression. Created by the Sumerians around 3500 BC, cuneiform began as a system of pictographs. Through repeated use over time, the pictorial representations became simplified and more abstract.
The first pictograms were drawn on clay tablets in vertical columns with a pen made from a sharpened reedstylus. Then two developments made the process quicker and easier: People began to write in horizontal rows (rotating counter-clockwise all of the pictograms 90° in the process), and a new wedge-tipped stylus was used which was pushed into the clay, producing wedge-shaped ("cuneiform") signs. By adjusting the relative position of the tablet to the stylus, the writer could use a single tool to make a variety of impressions.
Cuneiform tablets could be fired in kilns to provide a permanent record, or they could be recycled if permanence was not called for. Many of the tablets found by archaeologists were preserved because they were baked when attacking armies burned the building in which they were kept.
Invented by the Sumerians to record the Sumerian language, cuneiform was subsequently adopted and adapted by the Akkadians, Babylonians, Elamites, Hittites and Assyrians to write their own languages and was widely used in Mesopotamia for about 3000 years, though the syllabic nature of the script as it was refined by the Sumerians was unintuitive to the Semitic-language speakers. This fact, before Sumerian civilization was rediscovered, prompted many philologists to suspect a precursor civilization to the Babylonian.
Most later adaptations of Sumerian cuneiform preserved at least some aspects of the Sumerian script. Written Akkadian included both phonetic symbols from the Sumerian syllabary, together with logograms that were read as whole words. Many signs in the script were polyvalent, having both a syllabic and logographic meaning. When the cuneiform script was adapted to writing the Hittite language, a layer of Akkadian logographic spellings was added to the script, with the result that we no longer know the pronunciations of many Hittite words conventionally written by logograms. The complexity of the system bears a resemblance to classical Japanese, written in a Chinese derived script; some of these Sinograms were used as logograms, others as phonetic characters. Contemporary Japanese graphically distinguishes the logograms (kanji) from syllabary characters (kana) but otherwise retains a similar system.
The complexity of the system prompted the development of a number of simplified versions of the script. Old Persian was written in a subset of simplified cuneiform characters, that formed a simple, semi-alphabetic syllabary, using far fewer wedge strokes than Assyrian used, together with a handful of logograms for frequently occurring words like "god" and "king." The Ugaritic language was written using the Ugaritic alphabet, a standard Semitic style alphabet (an abjad) written using the cuneiform method.
The use of Aramaic became widespread under the Assyrian Empire and the Aramaean alphabet gradually replaced cuneiform. The last known cuneiform inscription, an astronomical text, was written in 75 AD.
Rawlinson correctly deduced that the Old Persian was a syllabic script and he successfully deciphered it. Working independently of him, the Irish Assyriologist Edward Hincks also contributed to the decipherment. After translating the Persian, Rawlinson and Hincks began to decipher the others. They were greatly helped by Paul Émile Botta's discovery of the city of Niniveh in 1842. Among the treasures uncovered by Botta were the remains of the great library of Assurbanipal, a royal archive containing tens of thousands of baked clay tablets covered with cuneiform inscriptions.
By 1851, Hincks and Rawlinson could read 200 Babylonian signs. They were soon joined by two other decipherers: a young German-born scholar called Julius Oppert, and the versatile British Orientalist William Henry Fox Talbot. In 1857 the four men met in London and took part in a famous experiment to test the accuracy of their decipherments.
Edwin Norris, the secretary of the Royal Asiatic Society, gave each of them a copy of a recently discovered inscription from the reign of the Assyrian emperor Tiglath-Pileser I. A jury of experts was empanelled to examine the resulting translations and assess their accuracy.
In all essential points the translations produced by the four scholars were found to be in close agreement with one another. There were of course some slight discrepancies. The inexperienced Talbot had made a number of mistakes, and Oppert's translation contained a few doubtful passages due to his unfamiliarity with the English language. But Hincks' and Rawlinson's versions were virtually identical. The jury declared itself satisfied, and the decipherment of Akkadian cuneiform was adjudged a fait accompli.