Tyrtaeus in Wikipedia
Tyrtaeus (also Tyrtaios, Greek: Τυρταῖος) was a Greek elegiac poet who lived at Sparta about the middle of the 7th century BC.
According to the older tradition, Tyrtaeus was a native of the Attic deme of Aphidnae, and was invited to Sparta at the suggestion of the Delphic oracle to assist the Spartans in the Second Messenian War. According to a later version, he was a lame schoolmaster, sent by the Athenians as likely to be of the least assistance to the Spartans.
A fanciful explanation of his lameness is that it alludes to the elegiac couplet, one verse of which is shorter than the other. According to Plato the citizenship of Sparta was conferred upon Tyrtaeus, although Herodotus makes no mention of him among the foreigners so honoured. Basing his inference on the ground that Tyrtaeus speaks of himself as a citizen of Sparta, Strabo  is inclined to reject the story of his Athenian origin. The Suda speaks of him as "Laconian or Milesian"; possibly he visited Miletus in his youth, where he became familiar with the Ionic elegy.
Georg Busolt, who suggests that Tyrtaeus was a native of Aphidnae in Laconia, conjectures that the entire legend may have been concocted in connection with the expedition sent to the assistance of Sparta in her struggle with the revolted Helots at Ithome (464). However this may be, it is generally admitted that Tyrtaeus flourished during the Second Messenian War (c. 650 BC)--a period of remarkable musical and poetical activity at Sparta, when poets like Terpander and Thaletas were welcomed--that he not only wrote poetry but served in the field, and that he endeavoured to compose the internal dissensions of Sparta by inspiring the citizens with a patriotic love for their fatherland.
About twelve fragments (three of them complete poems) are preserved in Strabo, Lycurgus of Athens, Stobaeus and others. They are mainly elegiac and in the Ionic dialect, written partly in praise of the Spartan constitution and King Theopompus (Εὐνομία), partly to stimulate this Spartan soldiers to deeds of heroism in the field (Ὑποθῆκαι-the title is, however, later than Tyrtaeus). The interest of the fragments preserved from the Εὐνομία is mainly historical, and connected with the first Messenian war. The Ὑποθῆκαι, which are of considerable merit, contain exhortations to bravery and a warning against the disgrace of cowardice. The popularity of these elegies in the Spartan army was such that, according to Athenaeus, it became the custom for the soldiers to sing them round the camp fires at night, the polemarch rewarding the best singer with a piece of flesh. Of the marching songs (Ἐμβατήρια), written in the anapaestic measure and the Doric dialect, only scanty fragments remain.
The poetry of Tyrtaeus is considered representative of the genre of martial exhortation elegy. Scholar Elizabeth Irwin recognizes that adoption of language and thematic concerns of Homeric epic is characteristic of this genre. For instance, the words of Tyrtaeus 10.1-2 ("For it is a fine thing for a man having fallen nobly amid the fore-fighters to die, fighting on behalf of the fatherland") undoubtedly echo Hector's speech in 15.494-7 of Homer's Iliad.: ("And whoever hit by a missile or struck by a sword find his death and fated end, let him die. It is not unseemly for one to die protecting the land of his fathers"). Irwin further suggests that Tyrtaeus intentionally alludes to Homer in instances such as these for political reasons. Given the fact that Tyrtaeus' poetry, like that of other archaic authors, was most likely performed in the context of aristocratic symposia, it is possible that Tyrtaeus' references to epic heroism served to praise the elite status of his aristocratic audience..
Verrall definitely placed the lifetime of Tyrtaeus in the middle of the 5th century BC, while Schwartz disputed the very existence of the poet.. There are English verse translations by Richard Polwhele (1792) and imitations by H. J. Pye, poet laureate (1795), and an Italian version by F. Cavallotti, with text, introduction and notes (1898). The fragment beginning Τεθνάμεναι γὰρ καλόν (fr. 10 West) has been translated by Thomas Campbell, the poet. The edition by C. A. Klotz (1827) contains a dissertation on the war-songs of different countries.
 Tyrtaeus is the first author to describe the ideal of the citizen-soldier. His "Elegies" reflected what came to be a "permanent and timeless utterance" of the ideal of "arete", admired by the later Greeks including Plato. His cry that "no man is a good man in war, unless he can bear to see bloody slaughter and can press hard on the enemy, standing face to face..." was not just "a momentary outburst of warlike patriotism; they were the foundation of the whole Spartan cosmos."