Plato was born in Athens around 427 BCE. His aristocratic family background led him into a messy career in politics, which netted him a number of close calls and a permanent disillusionment with governmental pursuits. The death of Socrates (469–399 BCE), his teacher, was a catalyst for Plato, who embarked on a philosophical mission that blossomed into the founding of the Academy in about 387 BCE. The Academy was a great success (and an important point of origin for Western education); among Plato's pupils was Aristotle. Most of Plato's early work went toward a recreation, through dialogues, of the thinking of Socrates (who never wrote anything down), and much of Plato's later work built on that thinking. Thus, little is known about Socrates himself besides what is described by Plato, and much of that is blended with Plato's own ideas, motives, and recollections. Most accounts suggest that Socrates was an honored soldier in the Peloponnesian War, who spent much of the rest of his life wandering around Athens engaging in philosophical debates on the street. In any case, it seems clear that Socrates was put on trial and executed for being a religious subversive and for "corrupting the youth of Athens" (Socrates's speech at his trial and his conversation before death are re-enacted in Plato's Apology and Crito, respectively). The general consensus is that there was probably a political motive involved in his execution as well. There are many points in the Lysis, as in some of Plato's other Socratic dialogues, at which Plato seems to be attempting to exonerate Socrates, posthumously, of the charges for which he was executed.
There isn't a great deal of historical context necessary to the understanding of the Lysis, except a general grasp of how relationships between men and boys often functioned in Athenian life at the time (see Lover, in the Terms list). Nonetheless, it is sometimes helpful to recall that the Athens in which Plato wrote the Socratic dialogues was not a static, ideal state; Plato was writing about philosophical ideals, but his specific concerns and examples are often shaped by an awareness of the national and international power struggles that helped shape Athenian society. The same can be said of Socrates, whose major targets (according to Plato) often included the inflated traditional ideals of the ruling aristocracy. The Greek code of virtue and honor, based strongly in oral history (poetry) and religion, was generally seen as self- evident; it had certainly never been subjected to the kind of relentless analysis that Socrates developed. Both Socrates and Plato criticized and re- invented Athenian systems of value, and both ran into real-world trouble with the judicial and governmental structures in which those values were embodied (Plato in his early career in politics, Socrates at the end of his life). The Lysis is an intriguing instance of Plato working carefully, through Socrates, at one of the very centers of Athenian social life.
The Lysis is probably one of Plato's earlier dialogues, judging by its fairly uncompromising use of the Socratic elenchus and its ending in aporia. As Plato's series of dialogues develops, there is a clear shift in content away from the Socratic method and toward a more complex philosophical system that can only be Plato's own. Although the Lysis seems quite Socratic in its refusal really to assert anything in the end, it is still a text in which the voices of Socrates and Plato are bound together, the former as character and narrator, and the latter as author. The Lysis is also one of the least studied of Plato's works (though all of them have, of course, been studied quite a bit), primarily for two reasons: First, the Lysis does not provide a particularly exemplary version of the Socratic elenchus; no high ideals are offered for Socrates to dismantle, and his interlocutors are two young boys whose roles serve little purpose other than to agree with Socrates's successive theses and objections. Second, the Lysis does not show either Socrates or Plato moving clearly toward a cohesive philosophy. The dialogue proceeds, like many others, through a number of rejected hypotheses, and retains few clear assertions by the end. At a deeper level, the purely philosophical aims of the Lysis are compromised, in a fascinating way, by the situation in which they unfold (Socrates is demonstrating how to properly woo a beloved boy). Nonetheless, we can see Plato playing with some important notions, particularly in the areas of identity (likeness), harmony (with oneself and with others), and good and evil.