Samoan deverbal nominalizations show a crosslinguistically rare tripartite-inactive alignment where unaccusative, unergative, and transitive subjects are distinguished by inalienable genitive, alienable genitive, and ergative case, respectively, with objects being marked like unaccusative subjects (Mosel 1992). In addition, subject clitics exhibit a marked unergative alignment, where only unergative subject clitics are distinctly marked by alienable genitive case, whereas all other arguments receive inalienable genitive case. In this study, we demonstrate that these alignments follow naturally from a language-specific combination of independently established phenomena, including (i) prepositional ergativity (Polinsky 2016), (ii) split (in)alienability (Myler 2016; Alexiadou 2003), (iii) split-intransitivity, (iv) the unaccusative restriction on nominalizations (Imanishi 2014; Alexiadou 2001), and (v) a nonuniform nature of clitic pronouns (Bleam 2000), and therefore provides novel evidence for each of these phenomena. Comparing the distribution of ergative case in nominalizations crosslinguistically, we argue that the source of ergativity varies across languages and suggest that the split between syntactic and morphological ergativity cannot be reduced to a category-split of ergative subjects.
