The papal conclave held from 2 to 28 September 1823 ended with the election of Annibale della Genga to succeed the death recently deceased Pius VII as pope.

Pius VII, who had been elected in 1800, had an unusually long pontificate, during which the Catholic Church had faced, in the French Revolution and its aftermath, a severe attack on its power and legitimacy.

The zelanti were more radically reactionary than the politicani and wanted a highly centralised Church and vehement opposition to the secularising reforms that had resulted in France.

The politicani, though anti-liberal, were much more moderate and favoured a conciliatory approach to dealing with the problems that new ideologies and the incipient Industrial Revolution were creating.

It was only then that the eventual winner, Vicar of Rome Annibale della Genga, who was being promoted by the zelanti, began to gather support.