Demands increased with the two world wars of the 20th century, and foreign miners were brought in to compensate for shortage of French laborers.

A railway line connects these two towns, and extends from Carmaux eastward to Rodez and from Albi westward to Toulouse.

[1] Documents in the archives of Albi record that in 1245 the tolls on the Tarn bridge included one denier per donkey-load of coal.

[4] On 14 January 1744 a regulation was issued by the council of state that prohibited operating a mine without first obtaining a concession.

[3] The regulation confirmed that the king had full ownership of the subsoil of France, and that the mine operators were responsible for safety and for the working conditions of miners.

He had followed a military career until 1749, when his brother, the marquis de Carmaux, gave him the rights to the coal mines he owned in the area.

In 1752 Gabriel de Solages received a concession for mining within a radius on one league around his Blaye château.

[6] Gabriel de Solages invited Flemish miners to work his mines, but also employed local people.

A decree by the Committee of Public Safety of 24 Frimaire year III (13 December 1794) restored the lands and defined the limits of the 8,800 hectares (22,000 acres) concession.

[6] Oak timber used to support the sides and roofs of the galleries was found to decay quickly from dry rot.

An experiment with acacia wood reported in 1836 found it was much more durable in the same situation, unaffected after four years except at the sap-wood surface.

[9] In 1854 an imperial decree granted the Solages company a concession to build a railway connecting Carmaux to Albi at its own expense.

[10] The company was reorganized as the Société des Mines de Carmaux (SMC) in 1873, having sold the glass works and railway.

[14] During the 19th century industrial revolution the miners organized themselves and fought for shorter working hours, higher wages, improved safety and social insurance.

[7] Baron René Reille (1835–1898) was a member of the Comité des houillères, the coal mine owners' association, and president of the board of directors of the Compagnie minière de Carmaux.

"[18] In the election the Reille-Solages industrialists and the clergy opposed the Republican deputy Jean Jaurès (1859–1914), who was defeated by Reille.

Jaurès wrote that the Marquis de Solages had won election in the Carmaux constituency by implying to the workers that their jobs depended on his victory.

For if the company was unable to grant just two free days a week to a worker elected mayor by universal suffrage, it was because it consciously sought to destroy the effectiveness of the popular vote; it thus struck a blow at universal suffrage; and by making a mockery of the ballot, it criminally provoked the workers to violence.

[11] By mid-September Jaurès was writing that the company was breaking the law that made intimidating an elector by threat of dismissal from employment a criminal offense.

[24] Collections were organized to support the miners, whose determination, solidarity and discipline was widely admired by ordinary people.

[25] The politicians Duc-Quercy, Pierre Baudin, Alexandre Millerand, René Viviani, and Alfred Léon Gérault-Richard often spoke in Carmaux during the strike.

[23] Jean Jaurès, Duc-Quercy and Eugène Baudin said the strike was an attempt to guarantee the political liberties of Carmaux voters.

Paul Lafargue of the French Workers' Party saw it as part of the wider "political and economic battle against the bourgeoisie".

[26] On 18 October 1892 Millerand and Baudin attacked Reille in the Chamber of Deputies, accusing him of prolonging the strike to punish the workers by starvation.

Clemenceau went to Carmaux and arranged a compromise where Humblot would be moved to another mine and the convicted strikers would be released and given work.

"[29] Solages had resigned his seat as a deputy on 14 October 1892, and in January 1893 Jaurès won the resulting by-election on the Marxist Parti ouvrier français platform.

It introduced electric traction by trolley, mechanical haulage, hydraulic backfilling, electrification at the bottom favored by the absence of flammable firedamp.

At the same time organization of labour improved, the company searched for new outlets and adapted its products to commercial needs.

It includes a show mine opened in 2005 that lets visitors go 350 metres (1,150 ft) underground, a site on the European Route of Industrial Heritage.