See below for Libguides on related topics which will demonstrate how other parts of the Bodleian Libary can support your research in topics or periods of this area.
Suggested starting points are the following
MPEPIL divides its overview of the History of International Law into:
Of course don't limit your use of MPEPIL to these sections! It will have entries explaining the development of concepts (such as 'civilized nation'), on the history of specific topics within international law (eg Law of the Sea, history of), on particular treaties (eg Treaty of Tordesillas) and important cases (eg Aland Islands question) etc etc.
The Law Bod has the print copy of this encyclopedia at Internat 500 E56c, but the online version has had a number of updates since the work was printed.
are overviews such as the admittedly concise
Nussbaum A concise history of the law of nations (rev edn, 1962) Internat 510 N975a2
to the multi-volume
Verzijl et al International law in historical perspective at Internat 510 V574d (1968 - 1992)
v. 1. General subjects.--v. 2. International persons.--v. 3. State territory.--v. 4. Stateless domain.--v. 5. Nationality and other matters relating to individuals.--v. 6. Juridical facts as sources of international rights and obligations.--v. 7. State succession.--v. 8. Inter-state disputes and their settlements.--v. 9. pt. 9a. The laws of war.--v. 10. pt. 9b. The law of neutrality.--v. 11. pt. 9c. The law of maritime prize.
The Law Bod has a separate collection of public international law materials - treaties, court decisions, journals, monographs & text books. They are all distinguished by having shelf marks beginning Internat (short for international).
The books are subdivided into subjects as below. Although there is a shelf mark Internat 510 History do not think everything you need will be there. Early sources of, or works on the history of a specific topic within international law will be at that topic's shelf mark. Thus, a reproduction & translation of the 1563 work De re militari et bello tractatus by Pierino Belli (1502-1575) is shelved with works on War & armed conflict at Internat 750 B443
Internat 500 General and theory
Internat 510 History
Internat 520 Title to territory
Internat 530 The state (as a legal entity)
Internat 535 Dependent states and special regimes
Internat 540 State succession
Internat 545 Recognition
Internat 550 Servitudes
Internat 555 State responsibility
Internat 560 Jurisdiction of states
Internat 565 Nationality
Internat 570 Human rights
Internat 575 European Court of Human Rights: literature
Internat 580 International crimes
Internat 590 Economic law
Internat 600 Atomic energy
Internat 610 Social legislation and organisation
Internat 620 Transport and communications (except sea, air and space)
Internat 630 Law of the sea and waterways
Internat 640 Air law
Internat 650 Space law
Internat 660 International relations
Internat 670 Treaties (theory etc.)
Internat 680 History and general
Internat 681 General and regional political organisations
Internat 685 League of Nations: texts about the LN
Internat 687 United Nations: texts about about the UN
Internat 700 Peace and disarmament
Internat 710 General and theory
Internat 720 International courts and tribunals: general
Internat 725 Permanent Court of International Justice, International Court of Justice
Internat 730 Permanent court of Arbitration: literature
Internat 740 Individual arbitration tribunals: literature
Internat 750 War and armed conflict
Internat 760 Termination of war (including specific peace treaties)
To find general works on this topic, there are a couple of reassuringly intuitive subject search to use in SOLO
International law History
International law and relations -- History
If you would like some help with SOLO, please try the Libguide below - and/or have a chat with a librarian when next in the Law Bod!
SOLO searches may well reveal lots of useful titles held in other parts of the Bodleian.
Chief among them will probably be our near neighbour the Social Science Library, which collections (among other topics) Politics and International Relations.
The Bodleian's history collections are extensive, consequently deployed across various reading rooms.
but there well may be others - such as those with an area focus, China, Latin America, United States...
Consult their web pages for details like opening hours & services, and check to see if one of their specialists has written a Libguide which could help.
For the post 1945 international legal system, the guides below should be helpful: