The ancient Romans referred to the Etruscans as the Tusci or Etrusci. Their Roman name is the origin of the terms "Tuscany", which refers to their heartland, and "Etruria", which can refer to their wider region. In Attic Greek, the Etruscans were known as Tyrrhenians (Turrenoi, Turrhenoi, earlier Tursenoi Tursenoi), from which the Romans derived the names Tyrrheni, Tyrrhenia (Etruria), and Mare Tyrrhenum (Tyrrhenian Sea), prompting some to associate them with the Teresh (Sea Peoples). The word may also be related to the Hittite Taruisa. The Etruscans called themselves Rasenna, which was syncopated to Rasna or Rasna.  The origins of the Etruscans are mostly lost in prehistory, although Greek historians as early as the 5th century BC repeatedly associated the Tyrrhenians (Turrhenoi/Turrenoi, Tursenoi/Tursenoi) with Pelasgians. Thucydides, Herodotus and Strabo all denote Lemnos as settled by Pelasgians whom Thucydides identifies as "belonging to the Tyrrhenians" (to de pleiston Pelasgikon, ton kai Lemnon pote kai Athenas Tursenon), and although both Strabo and Herodotus agree that Tyrrhenus/Tyrsenos, son of Atys, king of Lydia, led the migration, Strabo specifies that it was the Pelasgians of Lemnos and Imbros who followed Tyrrhenus/Tyrsenos to the Italian Peninsula. The Lemnian-Pelasgian link was further manifested by the discovery of the Lemnos Stele, whose inscriptions were written in a language which shows strong structural resemblances to the language of the Tyrrhenians (Etruscans). Dionysius of Halicarnassus records a Pelasgian migration from Thessaly to the Italian peninsula, noting that "the Pelasgi made themselves masters of some of the lands belonging to the Umbri"; Herodotus describes how the Tyrrheni migrated from Lydia to the lands of the Umbri (Ombrikoi).  Strabo as well as the Homeric Hymn to Dionysus make mention of the Tyrrhenians as pirates. Pliny the Elder put the Etruscans in the context of the Rhaetian people to the north and wrote in his Natural History (AD 79):  Adjoining these the (Alpine) Noricans are the Raeti and Vindelici. All are divided into a number of states. The Raeti are believed to be people of Tuscan race driven out by the Gauls, their leader was named Raetus.

Answer this question "What is the origin of the Etruscan civilization?" by extracting the answer from the text above.
mostly lost in prehistory, although Greek historians as early as the 5th century BC repeatedly associated the Tyrrhenians (Turrhenoi/Turrenoi, Tursenoi/Tursenoi) with Pelasgians.