Gaius Marius was elected to the Tribune of the Plebians

Gaius Marius initially entered politics in 119 BC after achieving success in the military and cultivating some favorable relationships with Rome's elite. Due to his outstanding work in the position, he was later given the responsibility of leading the province of Spain.

Marius was reinstated as a plenipotentiary for the upcoming year in 120 BC. Metelli, specifically Lucius Caecilius Metellus Dalmaticus, helped him win. Although Plutarch claims that Metelli was a hereditary patron of his family, this claim may be a modern exaggeration. Prospective consuls frequently run campaigns for their preferred court nominees in an effort to lessen the possibility that opposing courts will use their veto power.

In 119 BC, he was elected to lead the election, and he enacted regulations that limited noble interference in elections. Following his election as praetor in 115 BC, he was appointed governor of more Spain, where he waged a war against outlaws. After his trip to Spain, he wed Julia, Julius Caesar's aunt.

Although some of his earlier decisions may have incensed certain groups of the populace, Marius was already recognized as a clever and inventive politician. The changes he makes are usually regarded as positive developments.