Diaspora mobilisation in conflicts is a multicausal phenomenon in which the cause-and-effect relationships are particularly complex, multidimensional and interlinked. Critical social and political developments, such as revolutionary or secessionist struggles, are often transformative events that influence diaspora consciousness and mobilise members to take action. At the same time, through their transnational practices diasporas shape the nature of conflicts, contribute to its exacerbation or promoting initiatives for non-violent actions, peacebuilding and reconciliation. By analysing the Syrian diaspora as a case, this study investigates how conflict dynamics as well as host country developments shape the emergence and process of transnational mobilisation of the Syrian diaspora in Germany. The main argument is that Syrian diaspora mobilisation is a dynamic process in which the interplay of internal and external factors shapes the opportunities and limits of transnational collective action at different stages of the conflict. The article is based on 70 in-depth interviews conducted with Syrian diasporic entrepreneurs in Germany between 2012-2016 and participatory observation of selected diaspora activities. The finding shows that the uprising in Syria, was a unifying factor as it inspired many Syrians abroad to take collective action to shape the origin countries future. As the conflict escalated, internal factors such as general mistrust, along with a fragmented solidarity, limited the ability to generate and maintain a common identity, becoming major stumbling blocks for diaspora mobilisation.