In Belgium, subnational levels are responsible for immigrant integration and have developed their own policies. Historically, francophone and Flemish political elites have taken opposing views on immigrant integration policy. However, regional policies have recently converged towards Flanders’ model, which involves a strong focus on compulsory civic integration. To understand this convergence and Wallonia’s utter shift, this paper investigates two hypotheses: politicization and policy learning. Building on Walloon parliamentary debates between 2004 and 2016, it argues that multilevel policy learning was critical in altering the debate on immigration integration towards a mandatory policy. Nevertheless, politicization of the issue, which has occurred as of 2009, constitutes both a necessary condition and a mutual reinforcement process for policy learning in Wallonia.