What is the the meaning of the title of Achebe's Things Fall Apart? What examples might support this answer?

The title
of  byderives from a line in a poem by William Butler Yeats, "The
Second Coming." The third and fourth lines of the poem are:

Things fall apart; the centre cannot hold;

Mere anarchy is loosed
upon the world ...

The significance of this has to do
with the Christian notion of the "second coming" of Christ. In Christianity, Christ
first entered the world in the Incarnation, when he was born of the Virgin Mary. According to
the Nicene Creed, "He shall come again with glory to judge both the quick and the
dead." Before the second coming of Christ, there is supposed to be a period of chaos and
general misfortune.

Achebe is writing about the arrival of British
colonialism and accompanying Christian missions causing chaos in Africa as they come into
conflict with traditional Igbo culture and religion. 

Yeats was an Irish poet
who supported the cause of Irish independence and was part of a revival of tradition Celtic
beliefs and folk culture, against what he saw as the cultural as well as political imperialism
of the English. Thus Achebe's title draws attention to the parallels between the English
oppression of Ireland and its oppression of Nigeria. 

represents both an
agent of the chaos engulfing his village and a victim of it. Probably the best example of the
chaos that unfolds with the destruction of the old religious order is when Enoch unmasks
an egwugwu. This leads to an anarchic clash among the villagers and Okonkwo's
suicide.