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Events on Wednesday 8 December 1869 1
1869First Vatican Council convenesRoman Catholic bishops gather at St Peter's BasilicaPope Pius IX opened the First Vatican Council, bringing together bishops from around the world at St Peter's Basilica in Rome. The council would go on to define the doctrine of papal infallibility the following year. It was the first ecumenical council held by the Catholic Church since Trent, three centuries earlier.