regex to parse out preceding backslash

regex to parse out preceding backslash

In JavaScript, I am trying to split a string by ';' if not preceded
(escaped) by '\'.
The string might look like:
asd;123;&auml\;;33;
So the above string should be split into:
asd
123
&auml\;
33
I thought [^\]; would do the trick but this selects the preceding
character of ';' as well if it is not a '\'. I want only the ';' though
without its preceding character.