Why did the Mandalorians not join the Rebellion?

Especially since it was the Empire that destroyed Mandalore and dispersed the Mandalorians across the galaxy after losing their home planet. One would expect their mutual hatred of the Empire would have unified them in standing against the Imperial forces.

Or was it that the Jedi (and their association with the Rebellion) being the Mandalorians’ long time enemy that kept the Mandalorians from joining the Rebellion?