Are RAID formats compatible across distributions?

I'm planning a NAS/home media server build, probably with a HP Proliant Microserver. It will probably have two HDDs in RAID 1, while the OS while run from a USB drive.

Question is: once I've set up the RAID drives, can I swap the OS for something completely different and expect it to keep working? Let's say swapping between FreeNAS, Ubuntu, Fedora, XPEnology...