Latin American history since the late nineteenth century has rarely been treated under the rubric of ‘settler colonialism’.1 While historical atlases and popular culture have long bewailed or feted Latin America as the world region of mestizaje (‘racial mixing’), the label ‘settler colonialism’ has typically been attached to English-speaking societies of predominantly white European descendants. The reasons for South America’s exclusion from the category may seem obvious enough for most of the continent, but they are much less so for the region that elsewhere I have called ‘the Western South Atlantic’: the land mass stretching down the Atlantic coast line from Southern Brazil to Patagonia, which Alfred Crosby included among his list of ‘Neo-Europes’.2 It is this region that this chapter will concentrate on in order to interrogate the usefulness of the category ‘settler colonialism’ for its historical study. Rather than focusing on the colonial period, which has received some attention by scholars of ‘settler colonialism’,3 I focus on the period since 1870, during which the region has received far more immigrants or settlers than during 300 years of Spanish/Portuguese rule. In José Moya’s terms, ‘by the eve of World War I there were more Spaniards in the city of Buenos Aires (306,000) than there had been in all of the Spanish colonies at any given time before the Wars of Independence’.4