Keeping in mind that \311 is the iso-8859-1 encoding of U+00C9, and that \303\211 is the UTF-8 encoding of the same character, you can see that XML::Simple properly extracts text from XML:

#!/usr/bin/perl

use strict;
use warnings;

use Data::Dumper qw( Dumper );
use XML::Simple  qw( );

$XML::Simple::PREFERRED_PARSER = 'XML::Parser';

my $latin1_xml = <<"__EOI__";
<?xml version="1.0" encoding="iso-8859-1"?>
<root>\311ric</root>
__EOI__

my $utf8_xml = <<"__EOI__";
<?xml version="1.0" encoding="UTF-8"?>
<root>\303\211ric</root>
__EOI__

my $xs = XML::Simple->new();
for my $xml ($latin1_xml, $utf8_xml) {
    my $tree = $xs->XMLin($xml,
        ForceArray => 1,
        KeepRoot   => 1,
    );
    local $Data::Dumper::Useqq = 1;
    print Dumper $tree;
}
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$VAR1 = {
          'root' => [
                    "\x{c9}ric"
                  ]
        };
$VAR1 = {
          'root' => [
                    "\x{c9}ric"
                  ]
        };
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It also outputs XML properly (albeit using a weird interface):

#!/usr/bin/perl

use strict;
use warnings;

use Data::Dumper qw( Dumper );
use XML::Simple  qw( );

my $tree = {
          'root' => [
                    "\x{c9}ric"
                  ]
        };

$XML::Simple::PREFERRED_PARSER = 'XML::Parser';

my $xs = XML::Simple->new();
for my $enc (qw( iso-8859-1 UTF-8 )) {
    my $xml = '';
    {
        open(my $fh, ">:encoding($enc)", \$xml) or die;
        $xs->XMLout($tree,
            XMLDecl    => qq{<?xml version="1.0" encoding="$enc"?>},
            KeepRoot   => 1,
            OutputFile => $fh,
        );
        close($fh);
    }
    local $Data::Dumper::Useqq = 1;
    print Dumper $xml;
}
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$VAR1 = "<?xml version=\"1.0\" encoding=\"iso-8859-1\"?>\n<root>\311ri
+c</root>\n";
$VAR1 = "<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n<root>\303\211ric
+</root>\n";
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