[1] Its passage and subsequent royal assent, this being a affirmation of responsible government in the colony, by the Governor General, James Bruce, 8th Earl of Elgin makes the bill a landmark piece of legislation in Canadian political history.

On February 28, 1845,[2] the representatives sitting in the Legislative Assembly unanimously adopted the text of an address asking Governor Metcalfe to take measures to compensate the inhabitants of Lower Canada whose properties were damaged or destroyed during the armed conflict of 1837–8.

On its part, the Special Council of Lower Canada had also issued an ordinance, in 1838, to indemnify certain parties, but on the basis of their presumed loyalty to the crown.

Following the adoption of the address to the governor in 1845, the Draper–Viger government set up, on November 24,[6] a commission to enquire into the claims the inhabitants of Lower Canada had sent since 1838, to determine those that were justified and provide an estimate of the amount to be paid.

The five commissioners, Joseph Dionne, P. H. Moore, Jacques Viger, John Simpson and Joseph-Ubalde Beaudry, submitted their first report in April 1846.

[8] The general election of January 1848 changed the composition of the House of Assembly in favour of the opposition party, the moderate reformists led by Robert Baldwin and Louis-Hippolyte Lafontaine.

[9] On March 7, governor Elgin called in Baldwin and Lafontaine, respectively leaders of the majority parties in both sections of the united province, to the Executive Council.

On January 29, 1849, Lafontaine moved to form a committee of the whole House on February 9 to "take into consideration the necessity of establishing the amount of Losses incurred by certain inhabitants in Lower Canada during the political troubles of 1837 and 1838, and of providing for the payment thereof".

Its members proposed various amendments to Lafontaine's motion: a first, on February 13, to report the vote within ten days "to give time for the expression of the feelings of the country";[12] a second one, on February 20, declaring that the House had "no authority to entertain any such proposition" since the Governor-General had not recommended that the House "make provision for liquidating the claims for Losses incurred by the Rebellions in Lower Canada, during the present session".

Tory MPPs Henry Sherwood, Allan MacNab and Prince attacked the legitimacy of the proposed measure because according to them it rewarded the "rebels" of yesterday and constituted an insult to the "loyal" subjects who had fought against them in 1837 and 1838.

[17]: 118 The English-language press of the capital (The Gazette, Courier, Herald, Transcript, Witness, Punch) participated in the movement of opposition to the indemnification measure.

George Moffatt was elected chairman and various public men such as Allan MacNab, Prince, Gugy, Macdonald, Rose and others gave speeches.

Certain liberal MPPs, including Louis-Joseph Papineau and Pierre-Joseph-Olivier Chauveau, opposed the amendment because, according to them, it resulted in the recognition, by the government, of the legality of the military court created by former acting governor John Colborne in order to speedily execute the prisoners of 1839.

Elgin's carriage was pelted with stones and rotten eggs, and by the evening a riot had developed which lasted for two days and involved thousands of people.