He led an abstemious life, maintaining himself in Rome by his painting Romantic landscapes, which were frequently combined with historical subjects. He also painted the scenes for an opera composed by himself . But he was constantly meditating on the political state of Italy. In 1830 he returned to Turin, and after his fathers death in 1831 removed to Milan. There he remained for twelve years, moving in the literary and artistic circles of the city and in 1834 helping to organise the "Salotto Maffei" salon there, hosted by Clara Maffei. He became the intimate of Alessandro Manzoni the novelist, whose daughter he married; thenceforth literature became his chief occupation instead of art, and he produced two historical novels, Niccolò dei Lapi and Ettore Fieramosca, in imitation of Walter Scott, and with pronounced political tendencies, his object being to point out the evils of foreign domination in Italy and to reawaken national feeling.
In 1845 d'Azeglio visited Romagna as an unauthorized political envoy, to report on its conditions and the troubles which he foresaw would break out on the death of Pope Gregory XVI. The following year he published his famous pamphlet Degli ultimi casi di Romagna at Florence, in consequence of which he was expelled from Tuscany. He spent the next few months in Rome, sharing the general enthusiasm over the supposd liberalism of the new pope, Pius IX; like Vincenzo Gioberti he believed in an Italian confederation under papal auspices, and was opposed to the Radical wing of the Liberal party. His political activity increased, and he wrote various other pamphlets, among which was I lutti di Lombardia (1848).
On the outbreak of the first war of independence, d'Azeglio donned the papal uniform and took part under General Durando in the defence of Vicenza, where he was severely wounded. He retired to Florence to recover, but as he opposed the democrats who ruled in Tuscany, he was expelled from that country for the second time. He was now a famous man, and early in 1849 Charles Albert, king of Sardinia, invited him to form a cabinet. But realizing how impossible it was to renew the campaign, and not having the heart to sign, in such wretched internal and external conditions, a treaty of peace with Austria (Correspondance politique, by E Rendu), he refused.
After the defeat of Novara (March 23 1849), Charles Albert abdicated and was succeeded by Victor Emmanuel II. D'Azeglio was again called on to form a cabinet, and this time, although the situation was even more difficult, he accepted, concluded a treaty of peace, dissolved the Chamber, and summoned a neW one to ratify it, The treaty was accepted, and d'Azeglio continued in office for the next three years. While all the rest of Italy was a prey to despotism, in Piedmont the king maintained the constitution intact in the face of the general wave of reaction. D'Azeglio conducted the affairs of the country with tact and ability, improving its diplomatic relations, and opposing the claims of the Roman Curia.
He invited Count Cavour, then a rising young politician, to enter the ministry in 1850. Cavour and Farini, also a member of the cabinet, made certain declarations in the Chamber (May 1852) which led the ministry in the direction of an alliance with Rattazzi and the Left. Of this d'Azeglio disapproved, and therefore resigned office, but on the king's request he formed a new ministry, excluding both Cavour and Farini. In October, however, owing to ill-health and dissatisfaction with some of his colleagues, as well as for other reasons not quite clear, he resigned once more and retired into private life, suggesting Cavour to the king as his successor.
For the next four years he lived modestly at Turin, devoting himself once more to art, although he also continued to take an active interest in politics, Cavour always consulting him on matters of moment. In 1855 he was appointed director of the Turin art gallery. In 1859 he was given various political missions, including one to Paris and London to prepare the basis for a general congress of the powers on the Italian question. When war between Piedmont and Austria appeared inevitable he returned to Italy, and was sent as royal commissioner by Cavour to Romagna, whence the papal troops had been expelled.
After the peace of Villafranca, d'Azeglio was recalled with orders to withdraw the Piedmontese garrisons; but he saw the danger of allowing the papal troops to reoccupy the province, and after a severe inner struggle left Bologna without the troops, and interviewed the king. The latter approved of his action, and said that his orders had not been accurately expressed; thus Romagna was saved. That same year he published a pamphlet in French entitled De la Politique et du droit chrêtien au point de vue de la question italienne, with the object of inducing Napoleon III to continue his pro-Italian policy. Early in 1860 Cavour appointed him governor of Milan, evacuated by the Austrians after the battle of Magenta, a position which he held with great ability. But, disapproving of the governments policy with regard to Garibaldi's Sicilian. expedition and the occupation by Piedmont of the kingdom of Naples as inopportune, he resigned office.
The death of his two brothers in 1862 and of Cavour in 1861 caused d'Azeglio's great grief, and he subsequently led a comparatively retired life. But he took part in politics, both as a deputy and a writer, his two chief subjects of interest being the Roman question and the relations of Piedmont (now the kingdom of Italy) with Mazzini and the other revolutionists. In his opinion Italy must be unified by means of the Franco-Piedmontese army alone, all connection with the conspirators being eschewed, while the pope should enjoy nominal sovereignty over Rome, with full spiritual independence, the capital of Italy being established elsewhere, but the Romans being Italian citizens. He strongly disapproved of the convention of 1864 between the Italian government and the pope. The last few years of d'Azeglio's life were spent chiefly at his villa of Cannero, where he set to work to write his own memoirs. He died of fever in Turin on January 15, 1866.
Besides a variety of newspaper articles and pamphlets, d'Azeglio's chief works are the two novels Ettore Fieramosca (1833) and Niccolò dei Lapi (1841),and a volume of autobiographical memoirs entitled I Miei Ricordi, (D'Azeglio Memoirs - p. 1867) a most charming work published after his death, in 1866, but unfortunately incomplete.
There is a poetry contest organized by a cultural organization in Puglia (italian region) named after D'Azeglio