So the drum came off easily, you didn't have to back off the shoes using the Star Wheel?
And inside was dry, no leaking brake fluid or differential oil?
Assuming trans is in neutral, axle won't turn easily because it is connected to differential and drive shaft.
But it certainly could be bad bearing on that axle.
You need to drain differential and remove the cover, then remove the "C" clip from that axle.
You can then pull out the axle and replace bearing and seal.