And so, as late as August 1655, when Milton replied to Morus in his _Pro Se Defensio_, the evidence still is that, though he had more correct ideas by that time as to the amount and nature of Morus's responsibility for the book, and was aware of some other author at the back of Morus, he had not yet ascertained who this other author was, and still thought that the defamatory Iambics against himself, as well as the Dedicatory Epistle to Charles II., might be Morus's own.

It seems to me possible that not till after the Restoration did Milton know that the alleged "French Minister" at the back of Morus in the _Regii Sanguinis Clamor_ was Dr.Peter Du Moulin, or at all events that not till then did he know that the defamatory Iambics, as well as the main text, were that gentleman's.

The only person who could have put an end to the mystery completely was Du Moulin himself, and not till after the Restoration, as we have seen, was it convenient, or even safe, for Du Moulin to avow his handiwork.
Yet all the while, as Du Moulin himself hints in his confession of 1670, he had been, if we may so express it, close at Milton's elbow.
In 1652, when the _Regii Sanguinis Clamor_ appeared, Du Moulin, then fifty-two years of age, and knows as a semi-naturalized Frenchman, the brother of Professor Lewis Du Moulin of Oxford, had been going about in England as an ejected parson from Yorkshire, the very opposite of his brother in politics.

He had necessarily known something of Milton already; and, indeed, in the book itself there is closer knowledge of Milton's position and antecedents than would have been easy for Salmasius, or Morus, or any other absolute foreigner.
The author had evidently read Milton's _Tenure of Kings and Magistrates_ and his _Eikonoklastes_, as well as his _Defensio Prima_; he was aware of the significance given to the first of these treatises by the coincidence of its date with the King's Trial, and could represent it as actually a cause of the Regicide; he had gone back also upon Milton's Divorce Pamphlets and Anti-Episcopal Pamphlets, and had collected hints to Milton's detriment out of the attacks made upon him by Bishop Hall and others during the Smectymnuan controversy.

All this acquaintance with Milton, the phrasing being kept sufficiently indefinite, Du Moulin could show in the book without betraying himself.