No Power to anything

Went out in the mud this weekend in my 90 XJ 4.0 4x4. No issues, went to start it this morning and nothing. Not even a click. No power to anything, battery is good...what are the possible issues? Is there something I should look at that may be wet or full of mud that may cause this?

Should mention that it will not take a jump or when swapped out with a new battery no results...

check your terminals, i had the same issues, ended up being a loose ground connection on the terminal.

Bad Ground

Or a dead ignition switch. Do the headlights work? If not then check at the battery, clamps, and the fuse links at the little starter solenoid near the battery, and check that starter solenoid near the battery too. Also turn on the head lights and check the battery voltage, it may be dead under load, even if it shows 12 volts. Should have 12.75 volts on good battery.