He was one of eleven children of Rafael Casanova i Solà (1625–1682), a landowner of a rural estate in Moià, and Maria Comes i Sors († 1684), from Lliçà d'Amunt.

At the time of his birth, the Casanova family enjoyed a solid financial position based on farming and the trade of grain and wool to supply the powerful textile industry in the subvegueria of Moianès.

In the "marriage agreement", it stated that Rafael Casanova would not obtain possession of the assets of the Bosch family, but would only temporarily manage them while their children remain underage.

This way, Rafael Casanova, the young man who came from Moià, economically consolidated his ascending position in Barcelona, while the Bosch family got a son in law to manage their assets.

In 1703, maritime powers, England and Holland joined the House of Austria and declared war against the Two Crowns, Bourbon France and Spain.

The nominee could resign if his judiciary experience was not considered suitable; once appointed they were advised and supervised by the Consell de Cent, the general assembly of citizens.

The ministries were assigned based on social classes, with the result that the chief minister candidates in the bag only contained corresponding names of those who had the title of "Honored Citizen", a distinction given to only those locals that were significantly distinguished public service in Barcelona.

This policy worked effectively so lesser known citizens like the tailor Bartomeu Oliver, the sailor Macià Ros, or the barber Pere Torner governed Barcelona, as well as more renowned citizens such as nobleman Ramon de Codina o Antoni de Valencia, the lawyer Gabriel Bòria, the doctor Francesc Orriols and the merchant Jeroni Mascaró.

Advisers who disagreed with his methods and his violation of the laws, feared that the new Bourbon king of Spain would try to impose the same absolutist politics that his grandfather Louis XIV had applied in France.

Luckily it was ruled that the lawyer Rafael Casanova, who was then a widower and was about 46 years old should take his place; in the afternoon of that day two emissaries of the city announced his appointment.

On 30 March 1706, the Minister Rafael Casanova addressed Charles of Austria on behalf of the city offering the sacrifice of the lives of the locals in their defense, and finally on 2 April the king issued a statement agreeing to stay in Barcelona to resist the attack.

On 15 April they began bombing the inner city with firebombs and then undertaking operations aimed at the conquest of the fortress of Montjuic from which, once taken, they could force the surrender of the capital.

Months later, inquiries were made about what happened during the assault on Mont Juic; the Second Minister Francesc Gallart, who before the war had shown sympathy Philip, was removed from the lists of candidates for public office, and then banished from the city.

From that year he attended all meetings of the Hundred, and his name became part of the exclusive list of people who could be drawn to become chief minister of Barcelona, which took place in 1713.

Also in 1708, in recognition of his prestige and reputation, Rafael Casanova was one of the designated representative, with Manuel de Ferrer i Sitges and Cristòfor Lledó i Carreras, from Barcelona, that queen Elizabeth received during the wedding ceremony with King Charles of Austria.

For his part Philip V pledged in Article 13 of the Treaty of Utrecht, to grant the Catalans amnesty, but only the same rights and privileges that the inhabitants of the Crown of Castile.

After the Peace of Utrecht (1713) he participated in the Junta de Braços (parliament) in which Catalonia proclaimed the continuation of the war in defense of their constitutions the on 6 July 1713.

It ruled the city until he was wounded in combat when commanding a counterattack of the Barcelona milícia at the Sanint Peter front on the last day of siege, 11 September 1714.

He maintained contact with several that had been leaders of the city during the siege, as well as with the exiles in the Austrian Empire, and is credited with the authorship of a public manifesto addressed to king George II of Great Britain remembering the alliance between Catalonia and England which was published in 1736, the twenty-second year of our slavery.

Rafel Casanova died in 1743 and two years after, the English historian Tindal wrote in 1745: The Catalans, thus abandoned and given up to their enemies, contrary to faith and honour, were not however, wanting to their own defence; but appealing to Heaven, and hanging up at the High Altar the Queen’s solemn declaration to protect them, underwent the utmost miseries of a siege; during which multitudes perished by famine and the sword, many were afterward executed, and many persons of figure were dispersed about the Spanish Dominions and dungeons.His figure has become an icon of catalanism, regarding him as one of their great Patriots.

"[..] and the Honour of the British Nation, always renowned for the Love of Liberty, and for giving Protection to the Assertors of it, was most basely prostituted and a free and generous People, the faithful and useful Allies of this Kingdom, were betrayed, in the most unparalleled Manner, into irrevocable Slavery.