The papal conclave held from 31 July to 4 August 1903 saw the election of Cardinal Giuseppe Melchiorre Sarto to become pope in succession to Leo XIII, who had died on 20 July after a 25-year-long pontificate. Some 62 cardinals participated in the balloting. Emperor Franz Joseph of Austria asserted the right claimed by certain Catholic rulers to veto a candidate for the papacy, blocking the election of the leading candidate, Cardinal Secretary of State Mariano Rampolla. Sarto was elected on the seventh ballot and took the name Pius X.

Franz Joseph I or Francis Joseph I was Emperor of Austria, King of Hungary, and the ruler of the other states of the Habsburg monarchy from 2 December 1848 until his death in 1916. In the early part of his reign, his realms and territories were referred to as the Austrian Empire, but were reconstituted as the dual monarchy of the Austro-Hungarian Empire in 1867. From 1 May 1850 to 24 August 1866, he was also president of the German Confederation.