javascript "back" image within ASP.NET application

I love asp.net, but it's the simple things that can be really difficult.  Here's my latest challenge.  I have an image (btnBack) that I want the user to be able to click and (you guessed it) go back.  I set it up first as an image button and passed the js onclick information to it both via code-behind with attribute.add and with the OnClientClick function.  In both cases, the page refreshed, but did not go back (NOTE: i tried both window.history.back and window.history.go(-1)).  

i then moved to using a hyperlink around the image with href="#' and an onclick function, but same result.  to further test my onclick function, i wrote it up separately as "goBack()" and added a first step of an alert("function triggered") so that it looked like the function below:

    function goBack() {
        alert("function triggered");
        window.history.back;
    }

at this point the function worked, BUT if i remove the alert (and hence the user interaction), it does not work.  in case it was a timing issue, i tried using a settimeout, but this did not help either.  what a pain in the ass, i just want to access the browser's back button behavior without making a call to the server.  

thanks in advance for your assistance.

kmt