Many of the forms and practices of interwar internationalism were recreated under the auspices of the Nazi ‘New Europe’. This article will examine these forms of ‘Axis internationalism’ by looking at Spanish health experts' involvement with Nazi Germany during the Second World War. Despite the ambiguous relationship between the Franco regime and the Axis powers, a wide range of Spanish health experts formed close ties with colleagues from Nazi Germany and across Axis and occupied Europe. Many of those involved were relatively conservative figures who also worked with liberal international health organisations in the pre- and post-war eras. Despite their political differences, their opposing attitudes towards eugenics and the tensions caused by German hegemony, Spanish experts were able to rationalise their involvement with Nazi Germany as a mutually-beneficial continuation of pre-war international health cooperation amongst countries united by a shared commitment to modern, ‘totalitarian’ forms of public health. Despite the hostility of Nazi Germany and its European collaborators to both liberal and left-wing forms of internationalism, this phenomenon suggests that the ‘New Europe’ deserves to be studied as part of the wider history of internationalism in general and of international health in particular.