It began Process_start in 154 BC as a revolt Change_of_leadership of the Celtiberians of Numantia on the Douro .

The first phase of the war ended Process_end in 151 , but in 143 , war flared up again with a new insurrection Change_of_leadership in Numantia .

In that year , Quintus Caecilius Metellus Macedonicus tried and failed to take Conquering Numantia by siege Besieging , but subjugated Conquering all the other tribes of the Arevaci .

Scipio built Building a ring of seven fortresses around Numantia itself before beginning Process_start the siege Besieging proper .

The decisive Roman victory over Numantia ushered in Bringing an era of lasting peace in Hispania until the Sertorian War over half a century later .