The two tribunes Flavius and Marullus, are angry and upset with the commoners who have gathered to celebrate Julius Caesar's triumphs and they try to drive them home: "Hence! home, you idle creatures, get you home."
Marullus chides them and reminds them of the time they waited to see Pompey returning in triumph. He angrily rebukes them saying how can they be so fickle and ungrateful and celebrate Caesar's victory over Pompey:
"And do you now put on your best attire?(50)
And do you now cull out a holiday?
And do you now strew flowers in his way
That comes in triumph over Pompey's blood?
Run to your houses, fall upon your knees,(55)
Pray to the gods to intermit the plague
That needs must light on this ingratitude."
Flavius instructs Marullus to remove all the robes and decorations on the statues which adorn Rome even though it is the feast of Lupercal and asks him to disperse the crowds which have gathered to greet Caesar:
"let no images(70)
Be hung with Caesar's trophies. I'll about,
And drive away the vulgar from the streets;
So do you too, where you perceive them thick."
The reason why he does is this to keep in check the growing popularity and fame of Caesar. The tribunes are frightened that if Caesar becomes too popular and famous then he would become all powerful and rule over every one in a brutal and dictatorial manner:
"These growing feathers pluck'd from Caesar's wing
Will make him fly an ordinary pitch.
Who else would soar above the view of men
And keep us all in servile fearfulness."
Marullus and Flavius are Tribunes men. They are angry so they want to drive the commoners from the street because they didn’t like how they were all praising Caesar. Marullus and Flavius take down anything that is praising Caesar to further hinder the celebration of Caesar’s victory.