Alongside writers such as Jovan Skerlić, Radoje Domanović and Stevan M. Luković, Grol wrote many articles critical of King Alexander I in newspapers such as Dnevni list (Daily Paper) and Odjek (Echo).

After 1903, Grol continued to work with Skerlić, first as a journalist, and, from 1905 to 1909, as the editor of Dnevni list, which represented the left-wing ideals of the Independent Radical Party.

In 1922, he and Kosta Jovanović founded the Nedeljni glasnik (Sunday Herald), which called for constitutional reform, the lessening of centralism, and more political agreement between Croatia and Serbia.

He was a member of a Yugoslav coalition government consisting of Democrats, Radicals and the Slovene People's Party, and served as Minister of Education until 1929 when he reunited with Davidović and joined the opposition.

[1] Christian Science Monitor Central European correspondent, Reuben Markham, described Grol as "one of the most unimpeachable democrats in the Balkans.

In the first half of 1944, Serb politicians in the government-in-exile attempted to convince King Peter to appoint Grol to replace Božidar Purić as Prime Minister, but British pressure resulted in the appointment of a non-Serb, Ivan Šubašić, who would be willing to remove Draža Mihailović from his post as Minister of the Army, Navy and Air Force.

On 18 August 1945,[5] Grol resigned his cabinet post because the communists failed to observe the conditions that had been agreed upon with the government-in-exile when the unified government was established.

[6] Grol tried to re-publish the pre-war Democratic Party magazine called Demokratija, but was blocked by the Partisans.