He was a devoted patriot. Cassius appeals to his patriotism in 1, 2, Line 159. Ligarious calls him “Soul of Rome”. He takes as his motto, “Peace, Freedom & Liberty” (3, 1, Line 110). He expresses it to the people, “Not that I loved Caesar less but that I loved Rome more”. Finally Antony admits it in his final speech over the dead body of Brutus.

He was not at all practical. He was a philosopher rather than a man of action. There are many references to his bookishness, notably his reading when the ghost appears, to him. He was an impractical politician.

He was a theorist in government. He could not compromise. He believed in the republican form of government and could not see that the people wanted a monarchy. He was an absolute failure as a leader in the war because he would not raise money by any questionable means when it could be raised by no honourable means. Note his charges against Lucius Pella and Cassius in Act 4, Scene 3. He cannot make the best of things as they are and consequently cannot get on with other men.

He is a vain man, deeply conscious of his own rectitude. See 1,2, Lines 85—89, “If it be aught–death.  So too in the quarrel scene with Cassius he rather flaunts his own incorruptibility. His vanity is shown in another way where he is willing to let Antony speak at Caesar’s funeral. He is sure that Antony can do no harm after he, Brutus, has spoken. Moreover, it is his vanity which makes him susceptible to Cassius’ solicitations to enter the conspiracy.

He misreads the characters of all with whom he comes in contact. He failed to see that Caesar was the one man who could save Rome. He under valued Antony’s power and ability. He was surprised to find Cassius taking bribes. Note also how little he understood the mob when he delivered his oration.

He is a very poor general and makes the great mistake which results in their defeat at Philippi.

TITINIUS

O Cassius, Brutus gave the word too early;*
Who, having some advantage on Octavius,
Took it too eagerly: his soldiers fell to spoil,
Whilst we by Antony are all enclosed.   *V.3. 5 - 8

On the other hand he has personal bravery to a very high degree as witness his bearing on the battlefield and the coolness with which he addressed Caesar’s ghost. He was a stoic as he reminds us on several occasions but went against the stoic belief when he committed suicide rather than face capture. Thus his pride and fear of shame were stronger than his philosophy.

His gentleness is perhaps his most beautiful trait. This is shown in his scene with Portia and more particularly in his two scenes with Lucius. He is no match for Anthony in cleverness, nor for Cassius in the administration of affairs, but he towers above them both in moral goodness. 

The final words go to his foes:

ANTONY

This was the noblest Roman of them all:*
All the conspirators save only he
Did that they did in envy of great Caesar;
He only, in a general honest thought
And common good to all, made one of them.
His life was gentle, and the elements
So mix’d in him that Nature might stand up
And say to all the world ‘This was a man!'*

OCTAVIUS

According to his virtue let us use him,*
With all respect and rites of burial.
Within my tent his bones to-night shall lie,
Most like a soldier, order’d honourably.
So call the field to rest; and let’s away,
To part the glories of this happy day.*

Act V. 5. ll 68 – 81