This section of the Timeline of Quebec history concerns the events between the Union Act and the British North America Act.

1840s

• 1841 - The Act of Union is enforced by the British Parliament.
• 1844 - Establishment of the Institut canadien de Montréal on December 17.
• 1845 - Fondation of the Montreal Witness by John Dougall .
• 1847 - L'Avenir , the official journal of the Institut canadien is founded. It becomes the journal of the Parti rouge.
• 1848 - Article 41 of the Union Act is amended. It is now legal to use the French language in the Parliament and in the Courts.
• 1848 - Establishment of the Institut canadien de Québec.
• 1849 - The first responsible government was instituted, under the Liberal coalition of Robert Baldwin from Canada West and Louis-Hippolyte Lafontaine of Canada East. The first Prime Minister of United Canada is Louis-Hippolyte Lafontaine.
• 1849 - On April 25, The Parliament passes the Rebellion Losses Bill to compensate people who suffered property damages during the Rebellions of 1837 in Lower Canada. The same day, Loyalists burn down the Parliament of Canada in Montreal during a riot. See Burning of the Parliament (Montreal) .
• 1849 - On October 11, an Annexation Manifesto calling for the Province of Canada to join the United States is published in the Montreal Gazette.

1850s

• 1850 - Beginning of the French Canadian emigration to the United States. See French Canadian diaspora.
• 1851 - According to a census, the population of Canada West is now numerically superior to that of Canada East. Politicians of Canada West begin to battle for representation by population (rep-by-pop).
• 1852 - The Séminaire de Québec, the first institution of higher learning in Canada, receives its Royal Charter on December 8 from the British Parliament. It becomes the first French language university in America. See: Université Laval.
• 1854 - The seigneurial system of land tenance is abolished in Canada East.

1860s

• 1860 - The Victoria Bridge is the first bridge linking the Island of Montreal to the South Shore.
• 1864 - Leaders of the Parliament of Canada hold conferences on a confederation project, which will lead to the creation of the Dominion of Canada with the British North America Act.