The name is the past participle of the Genoese verb pestâ (Italian: pestare), which means to pound, to crush, in reference to the original method of preparation: according to tradition, the ingredients are "crushed" or ground in a marble mortar through a circular motion of a wooden pestle. This same Latin root, through Old French, also gave rise to the English noun pestle.Strictly speaking, pesto is a generic term for anything that is made by pounding; that is why the word is used for several pestos in Italy. Nonetheless, pesto alla genovese ("Genoese pesto") remains the most popular pesto in Italy and the rest of the world.
Pesto is thought to have two predecessors in ancient times, going back as far as the Roman age. The ancient Romans used to eat a similar paste called moretum, which was made by crushing garlic, salt, cheese, herbs, olive oil and vinegar together. The use of this paste in the Roman cuisine is mentioned in the Appendix Vergiliana, an ancient collection of poems where the author dwells on the details about the preparation of moretum. During the Middle Ages, a popular sauce in the Genoan cuisine was agliata, which was basically a mash of garlic and walnuts, as garlic was a staple in the nutrition of Ligurians, especially for the seafarers.The introduction of basil, the main ingredient of modern pesto, occurred in more recent times and is first documented only in the mid- 19th century, when gastronomist Giovanni Battista Ratto published his book La Cuciniera Genovese in 1863:
"Take a clove of garlic, basil or, when that is lacking, marjoram and parsley, grated Dutch and Parmigiano cheese and mix them with pine nuts and crush it all together in a mortar with a little butter until reduced to a paste. Then dissolve it with good and abundant oil.
