News of the restoration of the hierarchy by Pope Pius XI had not been well received in 1850 and the anger had evidently not been entirely placated by the first Archbishop of Westminster, Cardinal Nicholas Wiseman's attempts to assure the English people that the bishops were coming to England only to minister to the Catholics of England, not to invade and establish temporal power.
In Stockport, on June 29 a large mob attacked the Church of Sts. Philip and James; the parish priest managed to escape after hiding the Blessed Sacrament. The mobs piled up vestments, service books, and furniture in the street to burn. At another church, St. Michael's, the Host was desecrated.
Remember that the Gordon Riots occurred two years after the Catholic Relief Act of 1778--the threat of what the English people considered Papal Aggression continued to provoke fear and hatred two years after the minority group of Catholics in western England and eastern Wales opened chapels and practiced their faith. Anger at Irish Catholic immigrants in England fleeing the potato famine contributed to this violence, too.