Battlefields

 At the Battle of Ticinus:

Carthaginians surround Scipio's mounted officers as they hold up the eagle standards and shout unheard among howling trumpets, stuttering drums, yelling men, tramping feet, squealing elephants, screaming horses, whining arrows and hammering metal;

Scipio Africanus leads a cavalry troop to his father's rescue;

"...two men with the height and craggy features of Neldor..." (Time Patrol, p. 225), wearing GI armor and carrying guns, lead Carthaginian cavalry toward the eagles;

Everard and Van Sarawak of the Time Patrol approach on foot in Roman uniforms, carrying stunners, with a hundred armed Patrolmen "[a]round the horizon and up in the sky..." (p. 222).

Thus, an ancient battle and a temporal battle occur in the same place. An original timeline contained the Carthaginians and the Scipios. A second timeline also contained the Neldorians. A third timeline additionally contains the Patrolmen.

When Everard stuns a horse and Van Sarawak stuns a Neldorian, the Carthaginians and the remaining Neldorian flee and Africanus rescues his father.

At the Battle of Regnano:

Manson Everard, in the guise of an Anglo-Norman who has served in the Varangian Guard, has joined King Roger's army and offers to fight on the left flank, where, in timeline alpha, Lorenzo killed Roger's son, then Roger;

two of the Time Patrolmen hovering above detect Lorenzo and inform Everard through the communicator in his medallion;

leading Sicilians against Lorenzo's troop, Everard unseats a knight, then, in close combat, stuns Lorenzo who, however, remains on his horse but does not, of course, kill Roger or his son.

In both cases, Everard pulled rank to be the one who intervened on the battlefield.