In the eyes of his critics, Emperor Charles I, the last ruler of the Austro-Hungarian empire, was at best an incompetent fool, at worst a war criminal.

But in the Vatican's opinion he was a miracle-worker, and on Sunday Pope John Paul II will hold a ceremony in St Peter's Square at which Charles will be beatified, putting him on the home stretch to sainthood.

Since he became pope in October 1978, John Paul has created 482 saints and beatified another 1,337 people, more than all previous popes combined in the Roman Catholic Church's 2,000-year history.

But few individuals elevated to this status are more controversial than the last Habsburg emperor, who died in exile on the Portuguese island of Madeira in 1922 at the age of 34.

The miracle attributed to Charles concerns Sister Maria Zita Gradowska, a Polish-born Brazilian nun who is said to have recovered the power to walk in 1960 after praying to the late emperor.

Charles, who ruled from 1916 to 1918, also acquired a reputation in Catholic circles as a man of peace - he was supposedly the only European monarch who genuinely wanted to end the carnage of the first world war.

It is this image that many historians contest. Anton Pelinka, professor of political science at Innsbruck University in Austria, calls the beatification"ridiculous".

Under Charles's command, the Habsburg empire was allied with Germany against Britain, France, Italy, Russia and the US.

Charles personally led the empire's 20th army corps on the eastern front, while elsewhere Austrian forces used poison gas against the Italians.

According to the emperor's official beatification website,"no victory could give him satisfaction: the sight of all the destruction and mangled corpses was entirely unbearable for him".