Sert was commissioned in 1900 to paint the interior of the Vic Cathedral in the Province of Barcelona, Catalonia in murals, which took him more than 30 years to complete.

[1] In 1929 he was commissioned with the elaboration of a series of large forma canvases painted in his signature grisaille style intending to cover the walls of the reconverted San Telmo church in Donostia-San Sebastián; they portray different historic chapters of the Basques in an epic manner.

[1] Sert began an affair with the well-known pianist and patron of the arts Misia Godebska in 1908.

[7] In 1925, Sert met Georgian-Russian sculptor Isabelle Roussadana Mdivani, known as Roussy, who subsequently moved in with him and Misia.

[6] Sert began an affair with Roussy and later divorced Misia on 28 December 1927 to marry Mdivani.