VATICAN CITY - During history's longest papacy, Pope Pius IX pitted the Roman Catholic Church against a changing world: condemning emerging freedoms of speech and religion, confining Jews to Europe's last ghetto, condoning seizure of a Jewish boy to be raised as a Catholic.
When he died in 1878, revenge-seeking Italian liberals tried to dump his body into the Tiber River.
On Sunday, Pope John Paul II will beatify Pius in a twin ceremony with the 20th century's Pope John XXIII, advancing the two pontiffs to the church's last step before possible sainthood.
Jewish groups are bitterly protesting Pius' beatification. Even some Catholics are challenging the church's pairing of the rigidly traditional Pius with the widely popular John XXIII, who has his own critics among conservatives for convening the 1960s' tradition-overhauling Second Vatican Council.
''A beatification too far,'' a respected English Catholic weekly, The Tablet, said of Pius IX's beatification, calling it ''the work of a small group of ultraconservatives.''
''It can only be seen as a political move, designed to provide a conservative and reactionary counterweight to the beatification of John XXIII,'' The Tablet said.
''Really, I cannot understand it,'' says Elena Mortara, great-great niece of the Jewish boy, Edgardo Mortara, who was taken from his weeping father's arms in 1858 by papal police.
Pius ''has caused so much suffering,'' she told the Italian religious monthly Confronti. ''The wound of the 'Mortara case' still aches in my family, and in all our community.''
Church authorities took the 6-year-old Edgardo from his family in Bologna after a Catholic housemaid claimed to have baptized the boy when he appeared deathly ill. Under Pius' patronage, Edgardo grew up a church ward and later a priest.
''Even in the 19th century, actions such as the Mortara kidnapping were viewed with shock and condemnation,'' the U.S.-based International Jewish Committee for Interreligious Consultations said in a letter of protest to the Vatican in mid-August.
Supporters of Pius' beatification say the taking of Edgardo was justified by his baptism.
Opponents are ''using today's mentality to judge the facts of 150 years ago,'' said Monsignor Carlo Liberati, one of the Vatican clerics who shepherded Pius' cause to beatification.
John Paul II himself has noted the ''difficult'' era in which Pius served - one in which the church often came under literal attack by the rising forces of nationalism and anti-clericalism.
Pius' 31-year papacy saw the breakup of the centuries-old Papal States, but he managed to bring the Roman Catholic Church out of the tumult intact.
An adamant upholder of all church customs, the noble-born Pius enforced restrictions on Jews in Rome's ghetto until abolition of the Papal States freed the Jews in 1870. It was Europe's last enforced Jewish ghetto until Nazis brought back the idea a half-century later.
In 1864, Pius issued his landmark Syllabus of Errors, 80 sweepingly negative points condemning modern ideas such as freedom of speech and religion and separation of church and state.
Point 80 rejected the modern world itself, denouncing the idea that a pope should ''reconcile himself and come to terms with progress, liberalism and modern civilization.''
Pius also fostered the Catholic dogmas of papal infallibility and the Virgin Mary's immaculate conception, linking them in a way that Pope John Paul II called a ''service to the faith'' in 1996.
At the time, Pius' proclamation of papal infallibility prompted bitterly opposed dissenters to break away from the church - the church's last major schism until the one that followed John XXIII's Second Vatican Council.
The council went on to override much of Pius' Syllabus of Errors in an effort to make the church more accessible to ordinary people. The innovations included allowing Mass to be celebrated in local languages rather than Latin.
The liberalization John XXIII set in motion make him a mistaken leader in the eyes of many church conservatives.
In Italy, however, Catholics are hanging crepe ribbons and balloons to celebrate his relatively quick-paced beatification. The peasant-born John is still known here as simply ''The Good Pope'' - more for his kindly manner than for any matter of church doctrine.
Ironically, John XXIII's cause for beatification long had been counterbalanced with that of another conservative Pius, the World War II-era Pius XII.
But Jewish groups increasingly protested what they said was Pius XII's silence against the Holocaust, and church officials quietly let it be known this year that the wartime pope's beatification was off the calendar for 2000.
Pius IX's, with its then less-known Jewish issues, moved up.