Constantin was still a member of the Assembly following the election of 1841.
However, on May 20, 1842, Russian commissioner Alexander Osipovich Duhamel obtained that he be deposed as Postelnic and replaced with Știrbei.
Cantacuzino presented himself as a candidate in the princely election of December, but only managed 41 of 188 votes; the winner was Bibescu.
Initially, Bibescu promoted him, assigning him office as an Efor of the Wallachian schools, jointly with Filipescu-Vulpea and Mihalache Ghica.
Like his brother Grigore (who sat in the Assembly's committee for educational review), Constantin was a reactionary who objected to educational reform.
Still present in the Assembly in 1843, he soon rallied with the anti-Bibescu opposition, blocking his legislative projects.
He later chose to expatriate himself, although his family remained behind.
His eldest son, Ion C. (Iancu), was by then married to Maria, daughter of the numismatist and Russian spy Nicolae Mavros, making Constantin in-laws with politician Ion Ghica and with the Kotzebue family.

In June 1848, Wallachia's liberal revolution toppled Bibescu and installed a Provisional Government.
Two of Cantacuzino's three sons, Ion and Grigore, were enthusiastic participants in the events.
In the early stages, both Constantin and his Mavros daughter-in-law helped the radical Nicolae Bălcescu evade police round-ups at Telega.
On June 11, the day of revolutionary victory, he wrote to Bălcescu a congratulatory and "rather humble" letter.
During the subsequent weeks, the new regime sought to obtain recognition from the Sublime Porte.
The Cantacuzino home was also where the Provisional Government, represented by Ioan Voinescu II, welcomed Suleiman Pasha in August.

In September, following its radicalization, the revolutionary movement was repressed by an Ottoman–Russian expedition; at the time, Cantacuzino Sr had again fled for safety to Corona.
On September 21, he rode back to Bucharest, presenting his services to the Ottoman Army under Fuad Pasha; reportedly, he had been called back by Duhamel.
Favored by both Russian and Ottoman overseers, he was subsequently appointed Caimacam by Fuad, on September 22.
The short ceremony was witnessed by Ion Cantacuzino, who reportedly shouted out: "Father, do not accept this sort of offices!"

Constantin's ascendancy led to the mass arrest of revolutionary leaders, who were then kept under armed guard at Cotroceni Monastery.
His acts became the topic of a protest, submitted to Âli Pasha, the Ottoman Foreign Minister, by revolutionary agents Ion Ghica and Abdolonyme Ubicini.
According to Ghica, Âli informed them that Cantacuzino had only been appointed Caimacam because Reshid Pasha had mistaken him for his more reformist brother.
By then, the Revolution's triumvirate of Princely Lieutenants had dispersed: though Christian Tell and Nicolae Golescu suggested armed resistance, Ion Heliade Rădulescu resigned and retreated to his home, leaving the palace to be taken by Ottoman soldiers.

On September 24, Fuad and the Caimacam issued a deportation order for some of the core figures of the previous regime.
The list included Bălcescu, Heliade, Voinescu II, and Nicolae Golescu, alongside Costache Aristia, Cezar Bolliac, Ion C. Brătianu, Dimitrie Brătianu, Ștefan Golescu, C. A. Rosetti, and Ioasaf Znagoveanu.
Cantacuzino's other preoccupation as Caimacam was an investigation into looting and arson by rebellious peasants, for which purpose he founded and led a specialized boyar committee.
In tandem, he and Fuad ordered Neofit II to expel revolutionary sympathizers from the ranks of his Wallachian Orthodox Bishopric.
Assigning the direct supervision of education to Băleanu, Filipescu-Vulpea, and Petrache Poenaru, he initiated the purge of radical teachers, and, on November 1, personally ordered for all schools to be shut down.
Ordering the remnants of the revolutionary army, under Gheorghe Magheru, to disband, he took hold of the arsenal of weapons collected by the deposed Lieutenants.
He sent these arms to the Transylvanian Saxons, who used them in battle
Constantin was still a member of the Assembly following the election of 1841. However, on May 20, 1842, Russian commissioner Alexander Osipovich Duhamel obtained that he be deposed as Postelnic and replaced with Știrbei. Cantacuzino presented himself as a candidate in the princely election of December, but only managed 41 of 188 votes; the winner was Bibescu. Initially, Bibescu promoted him, assigning him office as an Efor of the Wallachian schools, jointly with Filipescu-Vulpea and Mihalache Ghica. Like his brother Grigore (who sat in the Assembly's committee for educational review), Constantin was a reactionary who objected to educational reform. Still present in the Assembly in 1843, he soon rallied with the anti-Bibescu opposition, blocking his legislative projects. He later chose to expatriate himself, although his family remained behind. His eldest son, Ion C. (Iancu), was by then married to Maria, daughter of the numismatist and Russian spy Nicolae Mavros, making Constantin in-laws with politician Ion Ghica and with the Kotzebue family.
In June 1848, Wallachia's liberal revolution toppled Bibescu and installed a Provisional Government. Two of Cantacuzino's three sons, Ion and Grigore, were enthusiastic participants in the events. In the early stages, both Constantin and his Mavros daughter-in-law helped the radical Nicolae Bălcescu evade police round-ups at Telega. On June 11, the day of revolutionary victory, he wrote to Bălcescu a congratulatory and "rather humble" letter. During the subsequent weeks, the new regime sought to obtain recognition from the Sublime Porte. The Cantacuzino home was also where the Provisional Government, represented by Ioan Voinescu II, welcomed Suleiman Pasha in August.
In September, following its radicalization, the revolutionary movement was repressed by an Ottoman–Russian expedition; at the time, Cantacuzino Sr had again fled for safety to Corona. On September 21, he rode back to Bucharest, presenting his services to the Ottoman Army under Fuad Pasha; reportedly, he had been called back by Duhamel. Favored by both Russian and Ottoman overseers, he was subsequently appointed Caimacam by Fuad, on September 22. The short ceremony was witnessed by Ion Cantacuzino, who reportedly shouted out: "Father, do not accept this sort of offices!"
Constantin's ascendancy led to the mass arrest of revolutionary leaders, who were then kept under armed guard at Cotroceni Monastery. His acts became the topic of a protest, submitted to Âli Pasha, the Ottoman Foreign Minister, by revolutionary agents Ion Ghica and Abdolonyme Ubicini. According to Ghica, Âli informed them that Cantacuzino had only been appointed Caimacam because Reshid Pasha had mistaken him for his more reformist brother. By then, the Revolution's triumvirate of Princely Lieutenants had dispersed: though Christian Tell and Nicolae Golescu suggested armed resistance, Ion Heliade Rădulescu resigned and retreated to his home, leaving the palace to be taken by Ottoman soldiers.
On September 24, Fuad and the Caimacam issued a deportation order for some of the core figures of the previous regime. The list included Bălcescu, Heliade, Voinescu II, and Nicolae Golescu, alongside Costache Aristia, Cezar Bolliac, Ion C. Brătianu, Dimitrie Brătianu, Ștefan Golescu, C. A. Rosetti, and Ioasaf Znagoveanu. Cantacuzino's other preoccupation as Caimacam was an investigation into looting and arson by rebellious peasants, for which purpose he founded and led a specialized boyar committee. In tandem, he and Fuad ordered Neofit II to expel revolutionary sympathizers from the ranks of his Wallachian Orthodox Bishopric. Assigning the direct supervision of education to Băleanu, Filipescu-Vulpea, and Petrache Poenaru, he initiated the purge of radical teachers, and, on November 1, personally ordered for all schools to be shut down. Ordering the remnants of the revolutionary army, under Gheorghe Magheru, to disband, he took hold of the arsenal of weapons collected by the deposed Lieutenants. He sent these arms to the Transylvanian Saxons, who used them in battle
Constantin Cantacuzino (died 1877)