You could read the text into a hash keyed by the chapter title then sort that

use strict;
use warnings;

my %chapters;
my $chapter_title;
while ( <DATA> )
{
    chomp;
    if ( m/^Chapter \w+/ )
    {
        $chapter_title = $_;
        next;
    }
    next unless $chapter_title;
    $chapters{$chapter_title} .= $_;
}

for ( sort {$a cmp $b} keys %chapters )
{
    print "$_\n$chapters{$_}\n";
}

__DATA__
Chapter One
There were lots of monkeys here and they ate all the bananas... 
lots more text up to hundreds of words.
Chapter Nine
This chapter has probably 1000 words. 
Chapter Two
Here is the text in the second chapter...
Chapter Five
Here is the text in the fifth chapter... 
every chapter is of differing length, some long some short.

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In reply to Re: Sort text by Chapter names by rnewsham
in thread Sort text by Chapter names by Bman70

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