Perl itself can't control anything in your browser. Perl just prints strings*. If a webserver runs the perl script, it takes the output of said script and sends it to the browser.

As the previous poster has pointed out, you need to output some HTML that includes some javascript that uses the history object. Or, if you know the URL of the previous page, you can use the Location header. Most browsers honor this request and send the browser to the page specified.

*This is an oversimplification of what perl does, but it's the fundamental function of Perl when used as part of the CGI.