Although historical accounts of international relations usually close the chapter of colonialism in the 1970s, anti-colonial struggles ensue, under the claim for implementation of the right to self-determination, in asymmetric conflicts marred by prolonged diplomatic processes. Meanwhile, national liberation movements (NLMs) have appealed to states, institutions, and an international network of experts and other social actors, for solidarity, recognition, allies, and material support, as in past struggles for the independence, e.g., of East Timor and Algeria. Addressing two contemporary examples, this research examines the cases of Palestine and Western Sahara, in protracted conflicts with Israel and Morocco, respectively the powers occupying, settling and exploiting these territories. Palestinians and Saharawis have engaged in both armed struggle and diplomacy, and in crucial geopolitical junctures, proclaimed the establishment of their states to then seek recognition. Negotiations initiated in the late 1980s have worked to dilute the very meaning of self-determination, as significant concessions are asked from the occupied while their territories are settled by the occupiers. Meanwhile, Palestinians and Saharawis have worked to consolidate state institutions and foreign relations, in a rights-based approach to resistance and struggle, and also dedicate to human rights advocacy by seeking protection for people under occupation or refuge and accountability for violations. Thus, international law is an essential platform. Yet, by taking stock of these and other cases of apparent neglect, the nature of international law itself and of the capitalist international system that bred it are under scrutiny in the origin of these peoples’ very plight. Hence, through Marxist approaches to International Relations and critical legal studies, this research examines these situations’ recent history and these actors’ tactics in order to grasp the challenges and opportunities found or created by their strategies. Data was collected in 2017 and 2018 through engagement with the civil society actors (CSAs) attending the sessions of the UN Human Rights Council, with participant observation and interviews with CSAs and diplomats, and analysis of reports and campaign materials. Research stays in the Saharawi and Palestinian refugee camps in Algeria and Lebanon and participation in various Online events have updated the analysis. The research finds Palestinians and Saharawis’ use of international law to be both pragmatic and compulsory moments of their fight against foreign domination, as anti-colonial revolutionaries such as Frantz Fanon and Mahdi ‘Amel have put it, in their movement of becoming the subjects of history through national liberation.