This is the 10684th most frequent Korean word.
군중에게
"To the crowd."
In this sentence, "군중에게" is used to indicate the group of people (crowd) to whom something (the leader) is necessary.
군중에게 리더가 필요합니다.
The crowd needs a leader.
Here, "군중에게" is used to mark the recipient (the crowd) of the speech.
군중에게 연설을 전달했다.
He delivered a speech to the crowd.
In this case, "군중에게" describes the group of people who were given motivation.