As a child, Jean-Baptiste-Éric Dorion had a fiery temperament that earned him the nickname of "enfant terrible" a name his political adversaries loved to use. His education did not progress beyond the elementary grades, but any academic lack was quickly compensated by his voracious appetite for reading. Around the age of 16, Jean-Baptiste-Éric studied English in Québec City and in 1842, began working as a sales clerk in Trois-Rivières.
In 1844, Jean-Baptiste-Éric Dorion settled in Montréal, where he immediately became part of the intellectual, journalistic and political scenes. He helped establish the Institut Canadien at the time. In 1847, he founded the newspaper L'Avenir, which would serve as his forum for five years. His views turned the clergy and both moderate and conservative politicians against him. He advocated annexation with the United States and the abolition of seigneurial tenure and favoured agricultural development, advanced education in commerce and industry, dissolution of the Union, and rejection of the confederation project. He stated:
I oppose Confederation because I foresee innumerable difficulties with the joint powers given to the local and general governments in several areas. These conflicts will always be resolved in favour of the general government and to the detriment of the often legitimate claims of the Provinces.
L'Avenir ceased publishing in 1852 and Jean-Baptiste-Éric Dorion left Montréal to settle in Durham South, near Drummondville, where he would begin his political life. He was elected to the legislative assembly in the 1854 election. He was defeated in 1858, but returned in 1861, where he remained until his death in 1866, at only 40 years of age.
Jean-Baptiste-Éric Dorion was the archetypal member of the "parti rouge" whom the French-Canadian political and clerical elite dreaded in the mid-19th century. Following the path of Louis-Joseph Papineau, he never tempered his ideological zeal. He worked hard, and his political opponents respected him not as much for his ideas as for his forthrightness and intellectual honesty.
- Sylvain, Philippe. "Dorion, Jean-Baptiste-Éric." Dictionnaire biographique du Canada. Vol. IX. [Québec] : Presses de l'Université Laval, 1977. P. 230-236.