Challenging influential perspectives that downplay the role of shared rebel constituencies, we argue that they represent important causes of rebel alliances. Yet, we theorize distinct effects for different types of constituency. While compatible political aspirations push both organizations with a common ideological constituency and those with a common ethnic constituency to ally, for co-ethnic organizations this cooperation-inducing effect is offset by a cooperation-suppressing effect due to their higher risk of inter-rebel war. Leveraging a novel dataset of alliances in multiparty civil wars (1946–2015), we find support for our theoretical expectations. Shared ideological constituencies have a larger and more robust positive effect on the probability of alliances than shared ethnic constituencies. Furthermore, we find that co-ethnic rebel organizations tend to establish informal alliances only, while organizations sharing an ideological constituency are drawn to formal alliances.

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群居之鸟会聚在一起吗？叛军选区和内战联盟

我们挑战那些淡化共同反叛选区作用的有影响力的观点，我们认为它们代表了反叛联盟的重要原因。然而，我们对不同类型的选区的不同影响进行了理论化。虽然兼容的政治愿望推动具有共同意识形态选区的组织和具有共同种族选区的组织结盟，但对于同族组织而言，这种合作诱导效应被合作抑制效应所抵消，因为它们之间发生叛乱战争的风险更高. 利用多方内战（1946-2015）中联盟的新数据集，我们找到了对我们理论预期的支持。与共同的种族支持者相比，共同的意识形态支持者对结盟的概率具有更大、更强大的积极影响。此外，