Variables written ... with a "^" sign and in braces ... are automatically global and available everywhere in your program, without needing to be declared.

So is any fully-qualified package-global (even under strictures):

c:\@Work\Perl\monks>perl -wMstrict -le
"{ package Foo;  $::bar = 'Baz';  sub p_bar { print $::bar; } }
 ;;
 Foo::p_bar;
 ;;
 { package Fiz;  sub new_bar { $::bar = 'Boff'; } }
 Fiz::new_bar;
 Foo::p_bar;
 ;;
 $::bar = 'Quux';
 print $::bar;
"
Baz
Boff
Quux
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