King Henry V, by Shakespeare

King Henry V attacked France in order to get a dukedom that was (supposedly) rightfully his. However, the real reason behind his attack was likely to follow the advice of his father - better to unite England in a foreign war than to allow it to slip into civil war again.

After an unlikely victory at Agincourt, Henry ended up conquering France, marrying King Charles' daughter, and ruling both countries.

Henry threatens the French city Harfleur which he has under siege. He was not exactly a nice person, was he?

If we begin the battery once again,
I will not leave the half-achieved Harfleur
Till in her ashes she lie buried.
The gates of mercy shall be all shut up,
And the flesh'd soldier, rough and hard of heart,
In liberty of bloody hand, shall range
With conscience wide as hell, mowing like grass
Your fresh fair virgins, and your flowering infants
What is it then to me, if impious war,
Array'd in flames like to the prince of fiends,
Do, with his smirch'd complexion, all fell feats
Enlink'd to waste and desolation?
What is 't to me, when you yourselves are cause,
If your pure maidens fall into the had
Of hot and forcing violation?....

If not; why, in a moment look to see
The blind and bloody soldier with foul hand
Defile the locks of your shrill-shrieking daughters;
Your fathers taken by the silver beards,
And their most reverend heads dash'd to the walls:
Your naked infants spitted upon pikes,
Whiles the mad mothers, with their howls confus'd,
Do break the clouds

Henry reflects upon the unhappiness that comes with power. The pomp is all pretty useless when it really matters.

Wherin thou art less happy, being fear'd,
Than they in fearing.
What drink'st thou oft, instead of homage sweet,
But poison'd flattery? O, be sick, great greatness,
And bid thy ceremony give thee cure!
Think'st thou the fiery fever will go out
With titles blown from adulation?
Will it give place to flexure and low bending?
Canst thou, when thou command'st the beggar's knee,
Command the health of it?

King Richard II, by Shakespeare

Richard II was deposed and eventually executed by Henry Bolingbroke (Henry IV).

Richard finds out almost none of his nobles have remained loyal to him, and that they've all given allegiance to Bolingbroke.

No matter where; of comfort no man speak:
Let's talk of graves, of worms, and epitaphs;
Make dust our paper and with rainy eyes
Write sorrow on the bosom of the earth.
Let's choose executors and talk of wills:
And yet not so, for what can we bequeath,
Save our deposed bodies to the ground?
Our lands, our lives, and all are Bolingbroke's,
And nothing can we call our own but death,
And that small model of the barren earth
Which serves as paste and cover to our bones.
For God's sake let us sit upon the ground,
And tell sad stories of the death of kings,
How some have been depos'd , some slain in war,
Some haunted by the ghosts they have depos'd,
Some poison'd by their wives, some sleeping kill'd;
All murder'd, for within the hollow crown
That rounds the moral temples of a king
Keeps Death his court, and there the antic sits,
Scoffing his state and grinning at his pomp,
Allowing him a breath, a little scene,
To monarchize, be fear'd, and kill with looks,
Infusing him with self and vain conceit,
As if this flesh which walls about our life
Were brass impregnable; and humour'd thus,
Comes at the last, and with a little pin
Bores through his castle wall, and farewell king!

Richard ponders while in prison.

Thoughts tending to ambition, they do plot
Unlikely wonders; how these vain weak nails
May tear a passage through the flinty ribs
Of this hard world, my ragged prison walls,
And, for they cannot, die in their own pride,
Thoughts tending to content flatter themselves
That they are not the first of fortune's slaves,
Nor shall not be the last; like silly beggars
Who sitting in the stocks refuge their shame,
That many have and others must sit there;
And in this thought they find a kind of ease,
Bearing their own misfortunes on the back
Of such as have before endur'd the like.