In the global public health discourse, involving men in maternal and neonatal health is regarded as crucial for positive outcomes in both health and development. In South Africa, health interventions designed to promote male partner involvement among low-income indigenous populations have been framed within social constructivist notions of masculinities and have produced mixed outcomes. This has necessitated calls to explore alternative approaches, including the need to decolonise men and masculinities studies in Africa. As part of one phase of formative research for a mixed-method project aimed at adapting a male involvement intervention for the context of Sesotho-speaking men and women in the Free State, we applied a multi-site case study research design and collected qualitative data using focus group discussions and key informant interviews. Verbatim-recorded transcripts were translated, transcribed, and thematically analysed with NVIVO 14. The results indicate that customary practices in pregnancy, delivery, and newborn care are not static and vary between families based on belief systems, socioeconomic status, geographical setting (peri-urban/rural), and kinship networks of care. Therefore, these practices and beliefs should be understood, affirmed, and contested within the complex African-centred material and immaterial worldviews on personhood in which they were generated, transmitted, rejected, or adopted. It is recommended that a decolonised approach to male partner involvement in this context must be cognisant of the intersections of racial and gendered power relations, contestations in beliefs and practices, the resilient effect of colonialism on indigenous gender systems, as well as contemporary global entanglements that inform North–South power relations on the best practices in maternal and newborn health in the public health sector in South Africa.