1 University of the Basque Country (UPV/ EHU), Barcelona, Spain 2 Universitat Autònoma de Barcelona (UAB), Barcelona, Spain Correspondence Mar Griera, Universitat Autònoma de Barcelona (UAB), Barcelona, Spain. Email: mariadelmar.griera@uab.cat Funding information Ministerio de Ciencia e Innovación, Grant/ Award Number: PID2020-120201GB-I00 Abstract Public debates and controversies on moral issues have gained visibility in recent decades in both Spain and Mexico. Conservative Catholic groups and networks are increas- ingly playing a crucial role in raising and framing highly morally charged themes in the public arena, especially on intimacy-related policies, including sexual and reproduc- tive freedoms. A new generation of young Catholic leaders becoming key political agents has emerged in this scenario. They are fostering new mobilisation repertoires in the public sphere (e.g., digital activism and public performances) and promoting new political narratives merging moral, cultural, and religious elements. These highly religious and conserva- tive young Catholics consider themselves part of a cultural/ cognitive minority and feel entitled to become what Howard Becker termed “moral entrepreneurs.” Most have been educated in Catholic schools and belong to Catho- lic movements. Still, they can also navigate secular politics and strategically use different regimes of justification and action. Within this context, the article aims to examine and compare the intersection of historical trends and the rele- vance of individual biographies to understand the role of these young Catholics in the public space in both countries. ORIGINAL ARTICLE “I'm going to do battle… I'm going to do some good”. Biographical trajectories, moral politics, and public engagement among highly religious young Catholics in Spain and Mexico Joseba García Martín 1,2 | Cecilia Delgado-Molina 2 | Mar Griera 2 DOI: 10.1111/soc4.13091 Received: 31 July 2022 Revised: 4 March 2023 Accepted: 8 March 2023 This is an open access article under the terms of the Creative Commons Attribution-NonCommercial-NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non-commercial and no modifications or adaptations are made. © 2023 The Authors. Sociology Compass published by John Wiley & Sons Ltd. Sociology Compass. 2023;17:e13091. https://doi.org/10.1111/soc4.13091 wileyonlinelibrary.com/journal/soc4 1 of 15