Tyrtaios was present in Sparta during the Second Messenian war. There has been talk that he was originally from Athens, but this now seems to be false. He mainly wrote marching songs and elegies. He used the Homeric tradition, but with a more corporate and collective ethos. Overall, he was present for the transition period of Sparta when she transformed into the militaristic state.

'The Spartans swore that they would take Messene or die themselves. When the oracle told them to take an Athenian general, they chose Tyrtaios, the lame poet, who rekindled their courage, and he took Messene in the twentieth year of the war.'
--Suda Lexicon

'And Philochoros says that when the Spartans overpowered the Messenians through the generalship of Tyrtaios, they made it a custom of their military expeditions that after the evening meal when the paean had been sung each man would sing a poem by Tyrtaios, and the leader would judge the singing and give the winner a prize of meat.'
--Athenaios, Scholars at Dinner

His Poetry

• SPARTAN SOLDIER
  It is beautiful when a brave man of the front ranks
  falls and dies, battling for his homeland,
  and ghastly when a man flees planted fields and
  city
  and wanders begging with his dear mother,
  aging father, little children and true wife.
  He will be scorned in every new village,
  reduced to want and loathsome poverty; and shame
  will brand his family line, his noble
  figure. Derision and disaster will hound him.
  A turncoat gets no respect or pity;
  so let us battle for our country and freely give
  our lives to save our darling children.
  Young men, fight shield to shield and never
  succumb
  to panic or miserable flight,
  but steel the heart in your chests with
  magnificence
  and courage. Forget your own life
  when you grapple with the enemy. Never run
  and let an old soldier collapse
  whose legs have lost their power. It is shocking
  when
  an old man lies on the front line
  before a youth: an old warrior whose head is white
  and beard gray, exhaling his strong soul
  into the dust, clutching his bloody genitals
  in his hands: an abominable vision,
  foul to see: his flesh naked. But in a young man
  all is beautiful when he still
  possesses the shining flower of lovely youth.
  Alive he is adored by men,
  desired by women, and finest to look upon
  when he falls dead in the forward clash.
  Let each man spread his legs, rooting them in the ground,
  bite his teeth into his lips, and hold.
  
  

• FRONTIERS
  You should reach the limits of virtue
  before you cross the border of death.