A leader must be with his unit to count. The only troops who do not require a leader are messengers and light cavalry. Should the leader be lost, the unit will halt for one turn. It will defend if attacked. The next turn, it will either move toward the nearest friendly unit with a leader, hold its ground, or retreat.
Units naturally move toward the nearest friendly unit.
If no friendly unit is within R3, the unit flips a coin. Head it holds, tails it retreats. The unit retreats until it gets within R3 of a leader. It will then proceed toward that leader. North Germans generally have one war chief per unit of 10 to 20 men.