How did the Athenian and Spartan poleis differ from each other?

Athens was a
true democracy for most of its existence, in which all governmental decisions were made by an
assembly of citizens. Any male natural born person could become a citizen; women and aliens were
excluded. All citizens were expected to attend meetings of the assembly; if one were seen in the
Agora (marketplace) while the assembly was meeting, he was normally marked
with red dye (applied by two slaves who carried a rope dipped in dye between them.) The dye
subjected him to public embarrassment, and also to a fine. Athenian democracy was not stable;
over time aristocratic citizens grew more and more powerful while small farmers often lost their
land and were forced to sell themselves in to slavery.

Sparta was situate in
an area known as Messenae. The Spartans did in fact require the Messenaen people (Helots) to
work as agricultural slaves. More importantly, the Messeanaens substantially outnumbered the
Spartans, so there was the constant threat of a revolt. It is for this reason that the Spartans
were quite militaristic. it is not that they were bellicose by nature; rather it was a matter of
survival.  They were not "freed" for military service while the Helots dutifully
worked the fields; it was the Helots whom the Spartans were required to keep under constant
vigilance.

Sparta was ruled by two kings from two rival families. They often
disagreed with each other. Their primary role was military leadership in battle. There was also
a council composed of twenty eight elders who were responsible for foreign and domestic policy.
There was an assembly comprised of all citizens, which in turn elected five Ephors,
or overseers who held substantial power.

Sparta did not
necessarily depend more on slaves than Athens; the Helots were held in servitude as a means of
keeping them subjected rather than a source for servants. Both poleis relied on slavery to a
substantial extent.

Women enjoyed more privileges in Sparta than in Athens,
although they were not allowed to wear jewelry or other ostentatious displays of wealth. It was
considered a privilege to be the wife of a victorious warrior.