ABSTRACT This article aims to demonstrate how the working class evolved and was organised in Palestine and Lebanon between 1920 and 1948. Palestine and Lebanon, which share characteristics such as being a part of the Ottoman Empire and being governed by mandates, also share similar experiences in combating sectarianism based on nationality or religion. The establishment of British rule in Palestine and French administration in Lebanon after World War I also influenced the trade union movement in these two countries: Nationalism flourished, trade unions became tools of politics, and the divide and rule policy of the colonial administration made organization difficult. Although these administrations were referred to as ‘mandates’ of the League of Nations, they actually experienced a colonization process and its effects similar to those in Africa. In this study, particularly the concept of colonization will be used, and the activities of trade unions in colonial regions will be examined through two Middle Eastern countries. While the Palestinian trade unions, which struggled against both British colonization and settler colonialism, were effective in preserving Palestinian identity, the Lebanese trade unions, dealing with French colonization as well as sectarianism, also managed to significantly preserve working-class unity.