Gaius’ radical actions after succession shocked everybody. He shocked the Senate, his family, even much of the people and mob. First Gaius made no action to deify his father even after his funeral. That was because he despised the imperial cult along with his stepbrother Drusus and wanted to nip it at its bud. Therefore he acknowledged (grudgingly) Augustus’ position as the son of a god (which made him grandson of a god though he would never admit it), but he was never elevated to actual divinity.
Livia of course was furious with him for this and he had to work hard to earn her forgiveness for being so reckless and politically stupid. He of course allowed her to keep the title of Augusta which had religious connotations of its own, but he would not accept for himself the title of Augustus which he said belonged only with his pious father. He was unworthy of it and he accepted only the titles of Princeps (senatus and civitatis) as well as Imperator.
The title of Pontifex Maximus he gave to Tiberius whom he felt was losing out since his son was excluded from the succession entirely, although Tiberius didn’t seem to mind. The title would also be promised to Nero Claudius Drusus (his son) when he died. Next he gave both his popular and militarily successful stepbrothers a lesser form of imperium maius that he inherited from his father in all the imperial provinces. To Drusus he promised that Germanicus would get the same (but only after his father’s death) as he was to be the next Princeps.
Next he went before the Senate and asked them to confirm Germanicus as his heir. Of course Livia had already done behind the scenes work for this and the vote was a mere procedure. Already Gaius had decided on a good cop bad cop approach against the Senate, impressing upon the Senators that he Gaius would be quite lenient towards them, while also letting them know subtly that if they didn’t deal with him, they would have to deal with his mother and her faction.
Germanicus was given the title Caesar which set a new legal precedent for succession in the Principate. Every Princeps would be obliged to go before the Senate to have his heir candidate confirmed. Every heir would then bear the title Caesar. Of course Caesar was Gaius’ actual name but his gesture was that anybody could be Princeps, it was not restricted to family.
Next he abolished the practice of putting the portraits of emperors on coins. All his coins and Roman coins henceforth would bear Roman gods or goddesses on the obverse with SPQR on the reverse. He of course recognized that the symbolic power of coin imagery could be abused in the future by possible usurpers and wanted to delegitimize the practice as soon as possible.
Drusus then approached him and asked permission for his second son Claudius to begin the cursus honorum. He had been denied by Augustus for writing a critical history of the civil war as well as being an embarrassment to the family as he was slightly disabled but Gaius knew the younger son of Drusus was in actual fact just as clever as his elder brother Germanicus. Claudius aged 23 was quickly appointed as a tribunus laticlavius serving in Spain.
He recalled Lucius Antonius, grandson of Mark Antony allowing him to return to Rome as he was impressed with his legal expertise and intelligence. He passed over Sejanus son of Strabo the former praetorian prefect to his father and selected a relative unknown to the position who would be much more loyal as a result.
In a public gesture, he recalled Ovid (the most popular poet in Rome possibly) who had been banished by Augustus, thus immediately giving the impression of utmost tolerance. Gaius wanted to encourage freedom of speech and criticism among artists, writers and intellectuals and he habitually engaged in debates behind the closed doors of the Senate with other senators. Publicly he proclaimed he would never punish constructive criticism of himself saying he has much to learn from others.
He also relaxed Augustus’ adultery laws, now those who commit adultery face only a steep fine payable to the state (amount dependent on their ability to pay) rather than potential capital punishment. This proved to be a lucrative source of funds for the imperial treasury. Members of his own family were not exempt whatsoever and would be fined multiple times without mercy in the upcoming years making many of them impoverished and dependent on the princeps for funds which also reduced the political risk they posed. Since he was generous with money for his family though this was not overly resented.
Gaius then formalized the Consilium Principis as an official high command made up of the consuls, available ex-consuls, the princeps, his heir and discarded the practice of hosting unofficial councils with “friends” of the emperor. Thus he hoped to lower the (gradually increasing) tone of flattery and cronyism that existed in his father’s days. This also had the result of granting deliberative decision-making back to the Senate whereas his father had centralized the process of presenting bills to the Senate through the Consilium Principis. Now however, the Council would only have leeway over military affairs.
Rome's "First" Council
In military matters, he sent a decree that instructed troops to swear loyalty only to SPQR, recognizing that otherwise troops would be even more dedicated to generals and strongmen rather than to any notion of a Roman state with rules of succession in the long run. He similarly abolished the post of imaginifer in the legions. Gaius greatly appreciated what he saw as the potentially powerful symbolism of an abstract Roman state that he wants to impress on people, which goes beyond mere individuals.
He then abolished Augustus’ expensive policy of subsidizing Italian families to have children since it was clearly not working and decided to use all the money to set up public schools for middle class Italian children instead. He would work with local towns and cities to improve urban literacy as much as possible and scholarships would be given to promising students to continue their study. The higher curricula for more advanced students would emphasize Greek mathematics, natural philosophy, as well as engineering. The lower curricular would emphasize Roman virtues, the Roman state and people, citizenship, and inculcate patriotism. Gaius greatly feared that the empire's expansion would dilute Romanitas which although he cared little about for himself, he felt was essential to maintaining a strong Roman state.
Next he created a new corps of men made up of former legionaries who would act as a centralized military intelligence agency for the princeps as well as secret police if need be. These he dispersed to the provincial frontiers requesting regular updates on the forces beyond the empire. They were to be called the Frumentarii (collectors of wheat) because they were often disguised as such when they conducted their business.
His first major challenge would soon arrive though. Mere weeks after his succession, he received reports that the legions of Pannonia and Germania had revolted.