Giovanni Ferrero has expanded his family's company beyond brands like Nutella and built a global powerhouse—especially through big acquisitions in the U.S.

Ferrero, the European confectionery giant behind Nutella and Ferrero Rocher, is set to acquire WK Kellogg Co ., the maker of Froot Loops and other classic American cereals, in a $3.1 billion deal, according to a press release issued Thursday.

Ferrero, the Italian candy company behind Ferrero Rocher and Nutella, agreed to a deal to buy WK Kellogg, according to a press release issued Thursday morning.