[3] His mother was the daughter of Alexis Boitelle, one of the main founders of the coal industry in the Nord department.

[2] After completing his secondary education Jean Plichon attended the École centrale des arts et manufactures of Paris, graduating in 1886 in 3rd place.

[6] After the death of his father in 1888, Plichon replaced him as a member of the General Council of the |Nord department, representing Bailleul.

[8] He became one of the leading industrialists of northern France, president of the Béthune, Blanzy and Sainte-Thérèse mining companies.

He played an important role in the Méline commission in 1892, which implemented protective duties for wheat producers.

In 1922 his report on the world economic situation advocated protection of French production from foreign competition.

In 1924 Jean Plichon was still president of the Compagnie des mines de Béthune and Louis Mercier was still director-general.

[1] For industries like metallurgy and coal mining, only a limited company can manage the huge amounts of capital investment required.

[8] Men such as the Plichons, although they did not belong to the rich industrial bourgeoisie, were able to build great fortunes due to their political and technical skills.