Franck Kessie and Andreas Christensen are Barcelona’s first signings of the summer.
Barcelona have announced their signings on free transfers.
Ivorian midfielder Kessie, 25, joins from AC Milan, while Danish defender Christensen, 26, comes in from Chelsea.
Both players have signed four-year deals and their releases clauses are set at 500m Euros (£430m).
Kessie played 224 times for the Rossoneri, scoring 39 goals, and helped the club to their first Serie A title in 11 years last season.
Christensen came through the youth academy at Stamford Bridge and played a total of 161 times for the Blues, while also spending two seasons on-loan at Borussia Monchengladbach.
He won the Champions League, Europa League, Uefa Super Cup and Club World Cup with Chelsea.
Brazil midfielder Philippe Coutinho has left the Nou Camp this summer, joining Aston Villa on a permanent deal for £18m, while forward Ousmane Dembele and right-back Dani Alves left after their contracts expired.
Meanwhile, Manchester United have reached a broad agreement over a 65m euro (£56m) fee, plus add-ons, with Barcelona for the Netherlands midfielder Frenkie de Jong.