Ronald Federico Araújo da Silva was born on 7 March 1999 in Rivera, Uruguay, to a Brazilian-Uruguayan father and a Brazilian mother. Originally a striker, he was switched to centre-back at seventeen, progressing through Rentistas (2016–17) and Boston River (2017–18) before Barcelona signed him in 2018 for €1.7 million plus add-ons.
After breaking through Barcelona B in 2019 he was promoted to the senior squad in 2020–21, taking the number 4 shirt and becoming the team's third captain by 2023. He has won La Liga in 2022–23 and 2024–25, the 2024–25 Copa del Rey, multiple Supercopas, and was named to the La Liga Team of the Season in 2021–22 and 2023–24. He extended his contract through 2031 in January 2025. A controversial early-game red card in the April 2024 UEFA Champions League quarter-final against PSG was a defining low point; a difficult appearance against Chelsea in November 2025 prompted him to step away briefly for a mental-health break.
Araújo has earned more than 25 caps for Uruguay since debuting in 2020 and helped his country to a third-place finish at the 2024 Copa América. A 1.91 m right-footed centre-back, he is regarded as a dominant 1v1 defender — Vinícius Júnior has called him "the best defender I have ever faced" — with elite recovery pace, aerial strength, and a willingness to defend high; the developmental edge for him remains in his ball-playing range.