There are many theories surrounding the origins of the spaghetti pasta, but the most plausible theory is that it was invented between 1000 and 1100 AD on the Italian island of Sicily. A manuscript called the Book of Roger was completed in 1154 and it detailed, among other things, the large-scale operation of what appeared to be spaghetti pasta manufacturing in the Sicilian town of Trabia.
The Book of Roger was written by an Arabian court chronicler named Abu Abdullah Mohammed al Idrisi and it contained a geographical survey of 12th century Sicily. One of the observations in the book was that the town of Trabia manufactured a pasta-like food product made from hard wheat and formed into long strands.
According to Idrisi's writings, the town manufactured what may actually be spaghetti in large quantities to be exported outside of Sicily, indicating that spaghetti-like pasta was unheard of outside of Sicily prior to this period.
The most popular theory about the invention of spaghetti is the one that involves the famous explorer Marco Polo. According to the legend, Marco Polo encountered noodles during one of his travels to China and took the recipe back with him to Venice. This theory, however, has been debunked by historians and the Book of Roger was completed a full century before Marco Polo was even born.