Robert Bellarmine was born in Montepulciano, Tuscany, in 1542. He entered the Society of Jesus and became one of the leading Catholic theologians of his age. After study and teaching, including a period in Leuven, he lectured in Rome. His extensive Disputationes defended Catholic teaching against Protestant arguments. He was made a cardinal in 1599.

Bellarmine was a major figure in the Catholic response to the Reformation, but he is also remembered for his involvement in Galileo's case. In 1616 he was instructed to inform Galileo that the heliocentric system could not be defended as established truth. Bellarmine later issued a written statement confirming that Galileo had not at that point been convicted of heresy or given a penance. Galileo's famous trial took place only in 1633, more than a decade after Bellarmine's death.

The cardinal also wrote extensively about the relationship between papal and secular authority, sometimes taking positions that proved controversial even in Rome. He died there in 1621, was canonised in 1930 and was declared a Doctor of the Church in 1931. His life remains closely connected with debates about faith, science and power.