A randoseru (ランドセル) is a firm-sided backpack made of stitched firm leather or leather-like synthetic material, most commonly used in Japan by elementary schoolchildren. Traditionally it is given to a child upon beginning his or her first year of school, whereupon the child uses the same bag until grade 6. The term is a borrowed word from the Dutch "ransel" meaning "backpack", a clue to its origins nearly 200 years ago as used in the Netherlands.
https://en.wikipedia.org/wiki/Randoseru
I heard Randseru is becoming popular among the adults in Europe ... I do not know if that is true.