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How did ships navigate 200 years ago? Not sure how accurate it was ?

How about using the stars? ... only at night ?

Use triangulation to known RF transmissions ( ie like direction finding of RF signals )

Geography recognition , rivers mountain's . towns etc ( Lidar ? )

Broadcast this info on some other secret frequency - drones only need to listen to the info

Use radar to track drone and broadcast its position to the item ...

The B-52 and SR-71 had star tracking systems for that exact reason. Not sure about the B-52 version but the SR-71 worked in daylight.

I wonder how satellites affect that now. So many more by an orders of magnitude

They don't.

Cloud cover, OTOH, is a real killer-- but not a problem for high altitude aircraft.

I wonder if weather balloons could be cheaply outfitted with star tracking and relay its position back down as a temporary GPS-like backup system.