he
combination came to mean as little as "envoy extraordinary"--though a
plenipotentiary _tout simple_ is still an agent, of no ceremonially
defined dignity, despatched with full powers to treat and conclude.
Finally, the evolution of the title of a diplomatist of the second rank
is crowned by the high-sounding combination, now almost exclusively
used, of "envoy extraordinary and minister plenipotentiary." The
ultimate fate of the simple title "resident" was the same as that of
"agent." Both had been freely sold by needy sovereigns to all and sundry
who were prepared to pay for what gave them a certain social status. The
"agent" fell thus into utter discredit, and those "residents" who were
still actual diplomatic agents became "ministers resident" to
distinguish them from the common herd.

The classification of diplomatic agents was for the first time
definitively included in the general body of international law by the
_Reglement_ of the 19th of March 1815 at Vienna[20]; and the whole
question was finally settled at the congress of Aix-la-Chapelle
(November 21, 1818) when, the proposal to establish precedence by the
status of the accrediting powers having wisely been rejected, diplomatic
agents were divided into four classes: (1) Ambassadors, legates,
nuncios; (2) Envoys extraordinary and ministers plenipotentiary, and
other ministers accredited direct to the sovereign; (3) Ministers
resident; (4) Charges d'affaires. With a few exceptions (e.g. Turkey),
this settlement was accepted by all states, including the United States
of America.

_Rights and Privileges of Diplomatic Agents._--These are partly founded
upon immemorial custom, partly the result of negotiations embodied in
international law. The most important, as it is the most ancient, is the
right of personal _inviolability_ extended to the diplomatic agent and
the members of his suite. This inviolability is maintained after a
rupture between the two governments concerned, and even after the
outbreak of war. The habit of the Ottoman government of imprisoning in
the Seven Towers the ambassador of a power with which it quarrelled was
but an exception which proved the rule. The second important right is
that of exterritoriality (q.v.), a convenient fiction by which the house
and equipages of the diplomatic agent are regarded as the territory of
the power by whom he is accredited. This involves the further principle
that the agent is in no way subject to the recei