The poet Shelley, upon hearing of the event wrote The Masque of Anarchy, which was banned for 30 years.
The full text (all 91 verses) can be seen here
Here are some selected verses:
"Ye who suffer woes untold,
Or to feel, or to behold
Your lost country bought and sold
With a price of blood and gold.
Let a vast assembly be,
And with great solemnity
Declare with measured words that ye
Are, as God has made ye, free.
Let the charged artillery drive
Till the dead air seems alive
With the clash of clanging wheels,
And the tramp of horses' heels.
Stand ye calm and resolute,
Like a forest close and mute,
With folded arms and looks which are
Weapons of unvanquished war,
And that slaughter to the Nation
Shall steam up like inspiration,
Eloquent, oracular;
A volcano heard afar.
Rise like Lions after slumber
In unvanquishable number,
Shake your chains to earth like dew
Which in sleep had fallen on you-
Ye are many - they are few."