The Duke of Wellington was a military hero, but he was much less popular as a politician, gaining the reputation of the Iron Duke. He suffered political and physical attacks as he obstructed the passage of the Reform Bill through the House of Lords.

On the evening of April 27, 1831, Wellington was out of town. [Apsley House] was attacked by rioters throwing stones. They broke thirty windows, at which point one of Wellington’s servants climbed onto the roof and fired two guns into the air, which dispersed the mob. On October 12, 1831, another reform mob stoned Apsley House. This time Wellington was at home. Wellington left the windows unrepaired until 1833, as a sign of contempt for efforts to intimidate him, although he did have iron shutters installed. https://shannonselin.com/2021/10/assassination-attempts-duke-of-wellington/

This song has the theme of reform which is often associated with the Whig Party. The official Reform Act was eventually passed in 1832 and it increased Britain's voters from 6% to 12% of the total population. https://digital.nls.uk/broadsides/view/?id=16745&transcript=1

The Triumph of Reform

Ye sons of Scotia, raise your voice,
And let the world hear ;            
We'll make the tyrants tremble,
For their day of judgment's near.
The glorious sun of Liberty
Is bursting into light;
And Wellington knows long ago,
How Britons they can fight.

       Success to noble Early Grey,
       Who still has brav'd the storm,
       With him we'll face our country's foe,
       And make them grant Reform.

Let Wellington think on the days
Of Spain and Waterloo,            
When the Shamrock, Rose and Thistle join'd
Great Bonny to subdue.
Although we never ran from him,
From our cause he ran away,
And like a traitor wanted to
Pull down the soldiers' pay.

       Success to noble Early Grey,
       Who still has brav'd the storm,
       With him we'll face our country's foe,
       And make them grant Reform.