Due to his success in Spain, Marius almost certainly returned to Rome in 113 BC with his personal wealth greatly enlarged. He received no triumph on his return, but he did marry Julia, the aunt of Julius Caesar. The Julii Caesares were a patrician family, but at this period seem to have found it hard to advance above the praetorship. The Julii had done so only once in the 2nd century, in 157 BC. The match was advantageous to both sides: Marius gained respectability by marrying into one most ancient patrician families in the Republic and the Julii received a great injection of energy and money. Sources are unclear on whether Marius joined the annual race of former praetors for the consulship, but it is likely that he failed to be elected at least once. The Jugurthine War started due to "Roman exasperation with the ambitions of Jugurtha", who had killed his half-brothers, massacred Italians in his civil war against them, and bribed many prominent Romans to support him in the Senate. After the start of hostilities, the first army sent to Numidia was apparently bribed to withdraw and the second army was defeated and forced to march under the yoke. These debacles eroded trust in the ability for the aristocracy to adequately manage foreign affairs. While Marius had seemingly broken with the Caecilii Metelli during his time as tribune and praetor, the Metellii did not seem to hold this rupture against him so much as to pass over him for selection as legate in the opening phases of the Jugurthine War. In 109 BC, likely to improve his chances for the consulship, Marius joined then-consul Quintus Caecilius Metellus, in his campaign against Jugurtha. Legates ("legati") were originally simply envoys sent by the Senate, but men appointed as legates by the Senate were used by generals as subordinate commanders, usually becoming the general's most trusted lieutenant. Hence, Metellus had to have asked the Senate to appoint Marius as legate to allow him to serve as Metellus' subordinate. In Sallust's long account of Metellus' campaign no other legates are mentioned, so it is assumed that Marius was Metellus's senior subordinate and right-hand man. Metellus was using Marius' strong military experience, while Marius was strengthening his position to run for the consulship.