Yes and no!
They will probably be physically able to fit, but there are a number of issues to consider:
Trigger voltage (these can vary I understand)
TTL metering (this generally only works with certains flashes and certain cameras which are designed for each other)
Auto Flash metering/power adjusting (same as above, but essentially the opposite)
Some flashes are very basic and just chuck out a wodge of light. Others are infinitely complex with IR range sensors, light meters, computers etc. all built in to work with the camera's onboard kit and adjust as necessary. Most occupy the middle ground and have a manual way of sliding a thingy to give an amount of light based on subject distance and aperture.
Some cameras are very basic and just have a couple of connection points which trigger the flash and need to be set manually to their sync speed (usually within 1/60 to 1/500th).
The best thing to do is post the exact model of flash and the camera you wish to use and we may be able to tell you if they work together.
The quickest thing to do is just try it, as I am under the impression that if the voltage trigger levels don't match it usually results in nothing happening, rather than an explosion or the damaging of your equipment. This advice is subject to you taking responsibility for any explosions or damage which occur and should not be followed.
Hope this helps,
Rob