The Turin club became the team first in Serie A, La Liga, Bundesliga, Ligue 1 or the Premier League to win eight consecutive league titles.
Ronaldo, meanwhile, became the first player to win the Premier League, La Liga and Serie A.
The day was a double cause for celebration as Juventus’ women’s team won their second straight league title since being founded in 2017.
Petronella Ekroth, Cristiana Girelli and Eniola Aluko wrapped up a convincing 3-0 victory over Verona to narrowly edge Fiorentina to the title by one point.
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Champions League hangover
Juventus looked like they were suffering a Champions League hangover following their shock midweek exit at the hands of Ajax, as Nikola Milenkovic put Fiorentina ahead early on.
But Alex Sandro pulled Juve level 30 minutes later, before Fiorentina defender German Pezzella diverted Ronaldo’s cross past his own goalkeeper to complete the comeback.
“I’m really happy that I won the Italian title in my first season,” said Ronaldo, who was signed for a reported $117 million in the summer. “Of course, it did not go well in the Champions League, but there is next year.”
The victory puts Juventus an insurmountable 20 points ahead of nearest rivals Napoli, wrapping up the league title with five games to spare.
Juve now boast 35 Scudettos, far ahead of closest challengers AC Milan who have 18.
The club’s recent dominance of Serie A began in the 2011-12 season when they won their first title since being stripped of two between 2004-2006 for match fixing.