In 157 BC, Marius was born in Cereatae, a small village near the Latin town of Arpinum in southern Latium.
The town had been conquered by the Romans in the late 4th century BC and was initially given Roman citizenship without voting rights (Civitas sine suffragio).
Only in 188 BC, thirty years before his birth, did the town receive full citizenship.
Although Plutarch claims that Marius' father was a labourer, this is almost certainly false since Marius had connections with the nobility in Rome, he ran for local office in Arpinum, and he had marriage relations with the local nobility in Arpinum, which all combine to indicate that he was born into a locally important family of equestrian status.
While many of the problems he faced in his early career in Rome show the difficulties that faced a "new man" (novus homo) in being accepted into the stratified upper echelons of Roman society, Marius – even as a young man – was not poor or even middle class, he was most assuredly born into inherited wealth gained, most likely, from large land holdings.
In fact, his family's resources were definitely large enough to support not just one member of the family in Roman politics: Marius' brother, Marcus Marius, would also enter Roman public life.

There is a legend that Marius, as a teenager, found an eagle's nest with seven chicks in it – eagle clutches hardly ever have more than three eggs; even if two females used the same nest – and finding seven offspring in a single nest would be exceptionally rare.
Since eagles were considered sacred animals of Jupiter, the supreme god of the Romans, it was later seen as an omen predicting his election to the consulship seven times.
 Later, as consul, he decreed that the eagle would be the symbol of the Senate and People of Rome.

In 134 BC, he joined the personal legion of Scipio Aemilianus as an officer for the expedition to Numantia.
It is unclear whether or not Marius was already present and serving in Numantia with the previous commander, Quintus Pompeius, the consul for 141 BC, when Aemilianus arrived.
However it is, while he was serving with the army at Numantia, his good services brought him to the attention of Scipio Aemilianus.
According to Plutarch, during a conversation after dinner, when the conversation turned to generals, someone asked Scipio Aemilianus where the Roman people would find a worthy successor to him, the younger Scipio gently tapped on Marius' shoulder, saying: "Perhaps this is the man".

It would seem that even at this early stage in his army career, Marius had ambitions for a political career in Rome.
According to Plutarch, as a hereditary client of the Caecilii Metelli, one of the noble families which was then emerging as the dominant faction in Rome, Marius ran for election as one of the twenty-four special military tribunes of the first four legions who were elected (the rest were appointed by the magistrate who raised the legion).
Sallust tells us that he was unknown by sight to the electors but was returned by all the tribes on the basis of his accomplishments.
After election, he likely served Quintus Caecilius Metellus Balearicus on the Balearic Islands helping him win a triumph.

Next, he possibly ran for the quaestorship after losing an election for local office in Arpinum.
The military tribunate shows that he was already interested in Roman politics before the quaestorship.
Perhaps he simply ran for local office as a means of gaining support back home, and lost to some other local worthy.
It is possible, however, that Marius never ran for the quaestorship at all, jumping directly to plebeian tribune.
He likely, however, participated in the major Roman victory of 121 BC which permanently cemented Roman control over southern Gaul.

In 120 BC, Marius was returned as plebeian tribune for the following year.
He won with the support of the Metelli faction, specifically Lucius Caecilius Metellus Dalmaticus.
According to Plutarch, the Metelli were one of his family's hereditary patrons; while this connection may be a latter-day exaggeration, it was not uncommon for prosp
In 157 BC, Marius was born in Cereatae, a small village near the Latin town of Arpinum in southern Latium. The town had been conquered by the Romans in the late 4th century BC and was initially given Roman citizenship without voting rights (Civitas sine suffragio). Only in 188 BC, thirty years before his birth, did the town receive full citizenship. Although Plutarch claims that Marius' father was a labourer, this is almost certainly false since Marius had connections with the nobility in Rome, he ran for local office in Arpinum, and he had marriage relations with the local nobility in Arpinum, which all combine to indicate that he was born into a locally important family of equestrian status. While many of the problems he faced in his early career in Rome show the difficulties that faced a "new man" (novus homo) in being accepted into the stratified upper echelons of Roman society, Marius – even as a young man – was not poor or even middle class, he was most assuredly born into inherited wealth gained, most likely, from large land holdings. In fact, his family's resources were definitely large enough to support not just one member of the family in Roman politics: Marius' brother, Marcus Marius, would also enter Roman public life.
There is a legend that Marius, as a teenager, found an eagle's nest with seven chicks in it – eagle clutches hardly ever have more than three eggs; even if two females used the same nest – and finding seven offspring in a single nest would be exceptionally rare. Since eagles were considered sacred animals of Jupiter, the supreme god of the Romans, it was later seen as an omen predicting his election to the consulship seven times.  Later, as consul, he decreed that the eagle would be the symbol of the Senate and People of Rome.
In 134 BC, he joined the personal legion of Scipio Aemilianus as an officer for the expedition to Numantia. It is unclear whether or not Marius was already present and serving in Numantia with the previous commander, Quintus Pompeius, the consul for 141 BC, when Aemilianus arrived. However it is, while he was serving with the army at Numantia, his good services brought him to the attention of Scipio Aemilianus. According to Plutarch, during a conversation after dinner, when the conversation turned to generals, someone asked Scipio Aemilianus where the Roman people would find a worthy successor to him, the younger Scipio gently tapped on Marius' shoulder, saying: "Perhaps this is the man".
It would seem that even at this early stage in his army career, Marius had ambitions for a political career in Rome. According to Plutarch, as a hereditary client of the Caecilii Metelli, one of the noble families which was then emerging as the dominant faction in Rome, Marius ran for election as one of the twenty-four special military tribunes of the first four legions who were elected (the rest were appointed by the magistrate who raised the legion). Sallust tells us that he was unknown by sight to the electors but was returned by all the tribes on the basis of his accomplishments. After election, he likely served Quintus Caecilius Metellus Balearicus on the Balearic Islands helping him win a triumph.
Next, he possibly ran for the quaestorship after losing an election for local office in Arpinum. The military tribunate shows that he was already interested in Roman politics before the quaestorship. Perhaps he simply ran for local office as a means of gaining support back home, and lost to some other local worthy. It is possible, however, that Marius never ran for the quaestorship at all, jumping directly to plebeian tribune. He likely, however, participated in the major Roman victory of 121 BC which permanently cemented Roman control over southern Gaul.
In 120 BC, Marius was returned as plebeian tribune for the following year. He won with the support of the Metelli faction, specifically Lucius Caecilius Metellus Dalmaticus. According to Plutarch, the Metelli were one of his family's hereditary patrons; while this connection may be a latter-day exaggeration, it was not uncommon for prosp
Gaius Marius