の人々

people

→ の
phrase Common #2,042
people 人々 means “people” and の links them to a preceding group, place, or identity, as in 日本の人々 (“Japanese people”). This expression is somewhat formal and is usually preceded by a noun or phrase.
JA: この町の人々はとても親切です。
EN: The people in this town are very kind.

パキスタンの人々の声

It’s the voice of the people of Pakistan.

— バジュランギおじさんと、小さな迷子 (2015)

そのグループの人々私たちといっしょに来た

The people from that group came with us too.

つまり英語はもはやイギリスの人々だけの言語ではないということです

In other words, English is no longer a language that belongs only to the people of Britain.