His studies were interrupted by the outbreak of World War I. Roman in 1915 went to Sankt Petersburg, working as a civil servant.

In 1918, Antoni Roman returned to Warsaw, finding a job at the Ministry of Trade and Commerce.

He was a Polish attache in the Free City of Danzig and participated in several diplomatic missions.

[1] Upon returning to Poland, he was named Minister of Trade and Commerce in the government of Felicjan Sławoj Składkowski.

He returned to Poland after the war, and took a job at the re-created Ministry of Trade and Commerce.