The legend of the Tarquins ran as follows. The Tarquins were of Greek extraction. Demaratus, their ancestor, belonged to the noble family of the Bacchiadae at Corinth, and fled from his native city when the power of his order was overthrown by Cypselus. He settled at Tarquinii in Etruria, where he had mercantile connections, for commerce had not been considered disreputable among the Corinthian nobles. He brought great wealth with him, and is said to have been accompanied by tile painter Cleophantus, and by Eucheir and Eugrammus, masters of the plastic arts, and likewise to have introduced among the Etruscans the knowledge of alphabetical writing. (Plin. H.N. xxxv. 5. s. 43; Tac. Ann. xi. 14.) He married an Etruscan wife, by whom he had two sons, Lucumo and Aruns. The latter died in the lifetime of his father, leaving his wife pregnant; but as Demaratus was ignorant of this circumstance, he bequeathed all his property to Lucumo, and died himself shortly afterwards. But, although Lucumo was thus one of the most wealthy persons at Tarquinii, and had married Tanaquil, who belonged to a family of the highest rank, the was excluded, as a stranger, from all power and influence in the state. Discontented with this inferior position, and urged on by his wife, he resolved to leave Tarquinii and remove to Rome, where a new eitizen had more chance of obtaining distinction. He accordingly set out for Rome, riding in a chariot with his wife, and accompanied by a large train of followers. When they had reached the Janiculum and were already within sight of Rome, an eagle seized his cap, and after carrying it away to a great height placed it again upon his head. Tanaquil, who was skilled in the Etruscan science of augury, bade her husband hope for the highest honour from this omen. Her predictions were soon verified. The stranger was received with welcome, and he and his followers were admitted to the rights of Roman citizens. He took the name of L. Tarquinius, to which Livy adds Priscus. His wealth, his courage, and his wisdom, gained him the love both of Ancus Marcius and of the people. The former appointed him guardian of his children ; and, when he died, the senate and the people unanimously elected Tarquinius to the vacant throne.

The reign of Tarquinius was distinguished by great exploits in war, and by great works in peace. The history of his wars is related very differently by Livy and Dionysius. According to the former writer he waged war with the Latins and Sabines with great success. lie first destroyed the wealthy town of Apiolae, which belonged to the Sabines, and subsequently took the Latin towns of Cameria, Crustumerium, Medullia, Ameriola, Ficulnea, Corniculum, and Nomentum. But his most memorable exploit was the defeat of the Sabines, who had advanced up to the very gates of Rome. They were at first driven back after a doubtful struggle, but were subsequently overthrown with great loss upon the Anio, and compelled to sue for peace. They ceded to the Romans the town of Collatia, where Tarquinius placed a strong garrison, the command of which he entrusted to Egerius, the son of his deceased brother Aruns, who, with his family, took the surname of Collatinus. Several traditions are connected with this war. The king's son, a youth of fourteen, slew a foe with his own hand, and received as a reward a golden bulla and a robe bordered with purple; and these remained in after times the ornaments and dress of youths of noble rank. In this war, also, Tarquinius is said to have vowed the building of the Capitol.

Livy says nothing more respecting the wars of this king, but Dionysius relates at great length his wars with the Etruscans. According to the latter writer five of the great Etruscan cities sent assistance to the Latins, which proved ineffectual; and subsequently all the twelve cities united their forces against Rome, but were overcome by Tarquinius, and compelled to submit to his authority. They are further stated to have done homage to him by presenting him with a golden crown, an ivory throne and sceptre, a purple tunic and robe figured with gold, and other badges of kingly power, such as the Etruscans used when their twelve cities chose a common chief in war. (Dionys. iii. 57, 59, 61.) Thus, according to this story, Tarquinius ruled over the Latins, Sabines, and Etruscans, as well as Romans; but no Latin writer mentions this war with the Etruscans, with the exception of Florus (i. 5), and the compiler of the triumphal Fasti. Cicero (de Rep. ii. 20) and Strabo (v. p. 231) relate that Tarquinius also subdued the Aequi ; but this war is not mentioned by Dionysius, and is referred by Livy (i. 55) to Tarquinius Superbus.

Although the wars of Tarquinius were of great celebrity, the important works which he executed in peace have made his name still more famous. Many of these works are ascribed in some stories to the second Tarquinius, but almost all traditions agree in assigning to the elder Tarquinius the erection of the vast sewers by which the lower parts of the city were drained, and which still remain, with not a stone displaced, to bear witness to his power and wealth. The quay by which the Tiber is banked, and through which the sewer opens into it, must clearly have been executed at the same time, and may therefore be safely ascribed to the elder Tarquinius.

The same king is also said in some traditions to have laid out the Circus Maximus in the valley which had been redeemed from water by the sewers, and also to have instituted the Great or Roman Games, which were henceforth performed in the Circus. The Forum, with its porticoes and rows of shops, was also his work, and he likewise began to surround the city with a stone wall, a work which was finished by his successor Servius Tullius. The building of the Capitoline temple is moreover attributed to the elder Tarquinius, though most traditions ascribe this work to his son, and only the vow to the father.

Tarquinius also made some changes in the constitution of the state. He added a hundred new members to the senate, who were called patres minorum gentium, to distinguish them from the old senators, who were now called padres majorum gentium. He wished to add to the three centuries of equites established by Romulus three new centuries, and to call them after himself and two of his friends. His plan was opposed by the augur Attus Navius, who gave a convincing proof that the gods were opposed to his purpose. [NAVIUS.] Accordingly he gave up his design of establishing new centuries, but to each of the former centuries lie associated another tinder the same name, so that henceforth there were the first and second Ramnes, Titles, and Luceres. He increased the number of Vestal Virgins from four to six.

Tarquinius had reigned thirty-eight years, when lie was assassinated by the contrivance of the sons of Ancus Marcius. They had long wished to take vengeance upon him on account of their being deprived of the throne, and now fearing lest he should secure the succession to his son-in-law Servius Tullius, they hired two countrymen, who, feigning to have a quarrel, came before the king to have their dispute decided; and while he was listening to the complaint of one, the other gave him a deadly wound with his axe. But the sons of Marcius did not secure the reward of their crime, for Servius Tullius, with the assistance of Tanaquil, succeeded to the vacant throne. Tarquinius left two sons and two daughters. His two sons, L. Tarquinius and Aruns, were subsequently married to the two daughters of Servius Tullius. One of his daughters was married to Servius Tullius, and the other to M. Brutus, by whom she became the mother of the celebrated L. Brutus, the first consul at Rome. The principal authorities for the life of Tarquinius Priscus are Livy (i. 34-41), Dionysius (iii. 46-73, iv. I), and Cicero (de Rep. iii. 20.).