The Battle of the Sabis, also (erroneously) known as the Battle of the Sambre or the Battle against the Nervians (or Nervii),is fought in 57 BCE in the area known today as Wallonia, between the legions of the Roman Republic and an association of Belgic tribes, principally the Nervii.
Julius Caesar, commanding the Roman forces, is surprised and nearly defeated.
According to Caesar's report, a combination of determined defense, skilled generalship, and the timely arrival of reinforcements allowed the Romans to turn a strategic defeat into a tactical victory.