Support for children's rights is greater among children raised in democratic environments. The present two studies examined children's endorsements and predictors of children's rights. Five democratic competences taken from the Council of Europe's Reference Framework of Competences for Democratic Culture served as predictors. We tested the models in a sample of children raised in five European countries and a sample raised in an African country, seeking to extend our model beyond the Global North. In Study 1, we found four of these five competences, namely, higher valuing of cultural diversity, civic‐mindedness, cultural openness and empathy significantly predicted higher endorsements of rights in children from Bulgaria, Italy, Norway, Romania and Spain (7–11‐year‐olds; N = 292). In Study 2, we found higher valuing of cultural diversity significantly predicted higher endorsements of rights in Nigerian children (7–14‐year‐olds; N = 84). Supporting Social Cognitive Domain Theory, children in both studies endorsed nurturance rights more than self‐determination rights. Inclusion of children from the Global North and South enabled us to determine whether patterns of rights endorsements were similar for children from both samples. Overall, this research presents novel findings on the salience of valuing cultural diversity in support for children's rights.