SOFTLY spoken, but possessed of a steely determination and a fierce intellect, Cardinal Joseph Ratzinger was preparing for retirement when he was called to the highest office of the Catholic Church.

Elected as Pope Benedict on April 19, 2005 when he was 78 – 20 years older than his predecessor, the late John Paul II, when he was chosen to head the Catholic Church, Benedict ruled over a slower-paced, more cerebral and less impulsive Vatican.

But he also had to deal with one of the most difficult periods of the Church's recent history, taking over at a time when the priest child abuse scandal was gathering pace with a flood of lawsuits and allegations pouring in from many countries.

Pope Benedict demanded the Church take responsibility for "sin within", apologised personally to victims and ordered an official inquiry into abuse in Ireland, which led to several bishops resigning.

But critics say he could have done more to prevent the scandal during his 24 years as head of the Congregation for the Doctrine of the Faith, which gave him direct oversight of some clerical abuse.

There was controversy over a lack of investigation into sexual abuse claims in the US, and last year his former butler Paolo Gabriele was found to be the source of leaked papers alleging Vatican corruption.