Jāzeps was raised in typical bourgeois traditions and from an early age was educated in foreign languages, piano play and painting.

In 1911 Grosvalds was drafted into Russian imperial army and spent his one-year service in cavalry regiment which was based in Lithuania.

Critical of the opportunities presented by the Munich art establishment, Grosvalds went to Paris in 1910, where he studied at several private academies (for example La Palette).

In summer of 1914, just before a war was breaking out over Europe, Grosvalds returned to Riga with several other Latvian painters Konrāds Ubāns, Voldemars Tone and Aleksandrs Drēviņš.

[2] In summer 1919 Grosvalds was demobilised and replaced his brother Olģerts as a secretary of Latvian delegation in Paris peace conference.