Fortunately for Englishmen, though no complete
work yet exists on this subject, the brilliant mono-
graphs of Professor Alison Phillips in the Cambridge
Modern History, as well as his lectures published in
the "Confederation of Europe," have already estab-
lished Castlereagh's position as a diplomatist; while
Sir Adolphus Ward chapters on the "Congress of
Vienna," also published in the Cambridge Modern
History, are the most impartial and authentic account
that at present exists of the Congress itself.

The acknowledgements, which I owe to a large
number of foreign historians and archivists, I must
reserve till the publication of my larger study. I can-
not forbear, however, from paying here a tribute to the
scholarship and learning of Professor August Fournier,
which he placed unreservedly at my disposal; and, like
all students of the modern papers at the Record Office,
I have experienced the great kindness and patience of
Mr. Hubert Hall and Mr. Headlam.

Nor could this little work, produced at such short
notice at a time of great pressure, have ever seen the
light at all, had it not been for the help and encourage-
ment of friends in London. To Mr. Alwyn Parker, the
Librarian of the Foreign Office, who suggested my
writing this work; to Dr. G. W. Prothero, the Director
of the Historical Section of the Foreign Office, who
brought into some shape and form my hastily con-
structed pages; and to Mr. Moreton Macdonald, Cap-
tain C. R. M. Cruttwell, and Dr. Headlam-Morley, who
gave me much valuable advice at a time when they were
overwhelmed with other important duties, I owe my
most grateful thanks, as well as to Major H. W. V.
Temperley, who, at considerable inconvenience to him-
self, procured me an interval in which to write.

The Bibliography merely gives a selection of a few
useful authorities. The documents in the Appendix
have been read with the original texts, and should
prove to be accurate.

CHARLES K. WEBSTER.

London, December 1918.

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