He hath brought many captives home to Rome Whose ransoms did the general coffers fill: Did this in Caesar seem ambitious?
You all did love him once, not without cause: What cause withholds you then, to mourn for him?
"I thrice presented him a kingly crown, Which he did thrice refuse: was this ambition? Yet Brutus says he was ambitious;"
(Act III, Scene II, Pg. 64) Caesar brought captives home to Rome, for the ransom payment was dues for the people to have their family back.
(Act III, Scene II, Pg. 64) Antony is trying to convince the Romans to feel sad about Caesar's death, rather than have the people side with Brutus. He's trying to convince them to understand his side and the hatred that rest within him over Caesar's murder.
(Act III, Scene II, Pg. 65) Antony explains to show how humble and good Caesar was by showing he doesn't deserve the crown, however, we knew this wasn't the case (Dramatic Irony).