In late 1859 and early 1860 Newman started to gather Catholic students in Oxford in order to form them to live with his Protestant fellows in the University of Oxford - that group became the seed of the Oxford Newman Society. In addition to this group, his idea was to found a branch of the Birmingham Oratory with a school close to the famous Universtity.
That attempt did not succeed because it incurred the general condemantion the Church had previously made on Catholic-Protestant mixed education. Therefore, a general meeting of the English Bishops held in December 1860 forbade Newman to continue his experiment.
In April 1866 the Bishop of Birmingham, William Bernard Ullathorne, requested a general permission from the Holy See to establish a mission at Oxford, without specifying that he planned to invite Newman to participate. That same month he warned Newman to prepare himself to take over the project.
As soon as he received the invitation, Newman wrote to his Anglican friend Edward B. Pusey, giving him the guarantee that he would not attack Anglicanism. Indeed, he wrote on April 29, 1866:
"I am grieved to think that it vexes you so much to hear of the chance of our going to Oxford. You may be sure we should not go to put ourselves in opposition to you, or to come in collision with the theological views which you represent" (W. Ward, Life of Cardinal Newman, vol. II, p. 121).
By the end of the year the Vatican gave the requested permission for the Oxford mission. Newman immediately went public and started fund-raising, offering the Vatican approval as pledge for his initiative.
When news of Newman's activity reached Rome, however, the Cardinals who issued the permission realized that it was not a question of sending some unknown missionary to help convert Anglicans to Catholicism, but of sending Newman to re-start his old agenda of a mixed education.
Hence, on March 22, 1867, Newman received a private message from Rome to stop any action on the project. Simultaneously, the Holy See sent a private instruction to Bishop Ullathorne ordering him to forbid Newman to move to Oxford.
Since Newman had stirred a lot of dust with his project, many well-placed persons in English society - Catholic parents of actual or potential Oxford students - had already either given donations to him or were ready to do so. The prohibition of the Holy See raised a strong discussion among them.
The Weekly Register of April 6, 1867 printed both the letter of its correspondent in Rome reporting that in Rome Newman was considered a partisan of Döllinger's theses (reproduced in the document 1 below), and an anomynous letter describing the supposedly secret instruction received by Bishop Ullathorne.
On that same April 6, a group of laymen gathered at the Stafford Club and issued a letter of solidarity with Newman, qualifying Rome's censure as "a blow that inflicts a wound upon the Catholic Church in this country" (ibid. p. 143). The letter ended with the signatures of about 200 well-known men and sparked many repercussions.
Regarding this state of affairs, Msgr. George Talbot from the Vatican wrote to Archbishop Manning, advising him to be strong and keep the laity in its proper place. This is our document 2, below.
Msgr. Talbot is quite clear when he speaks about Rome's suspicions of Newman - he considered Newman "the most dangerous man in England." His letter is also evidence of how Rome was well aware of what was happening in England and was encouraging Manning to act. It is interesting to note that one of Newman's obsessions was that Rome was always the victim of the intrigues of a radical Manning. This letter shows the opposite was true, that is, Manning had to be stimulated by the Vatican to act against Newman.
This letter is fundamental to see how Pius IX personally forbade Newman to continue with his inter-confessional plan of education.
These documents are in The Life of John Henry Cardinal Newman by Wilfrid Ward, vol. II, pp. 543-544 (document 1), pp. 146-148 (document 2).