Born into a family with a long-standing military tradition, Čolak-Antić was the great-grandson of Vojvoda Čolak-Anta Simeonović, a leader in the First Serbian Uprising against the Ottoman Empire.

Throughout his career, Čolak-Antić played an important role in Serbian and Yugoslav diplomatic affairs in the late 19th and early 20th centuries, contributing to the development of the region's foreign relations.

After earning a doctorate in law from the University of Geneva, Čolak-Antić entered diplomatic service in 1898, marking the beginning of a career that would see him occupy several key roles in Serbian and later Yugoslav foreign relations.

In the post-war years, Čolak-Antić continued his service as ambassador to Sweden and Romania, where he contributed to the formation of the Little Entente and the strengthening of Yugoslavia's diplomatic ties within Europe.

[4] His maternal grandfather was Dimitrije Matić, a prominent Liberal politician and philosopher who served as a minister and was president of the National Assembly when Serbia gained independence from the Ottoman Empire.

Čolak-Antić expressed concern to his government about secret talks between the Bulgarians and the Ottomans regarding unrest in Macedonia, which bypassed representatives of other communities: Serbian, Greek, and Vlach.

The rise of nationalistic visions led both countries to seek partitioning the Turkish territory and claiming it as historically theirs while preparing for war with the Ottoman Empire.

Čolak-Antić's mission in Bulgaria ended in 1903, the same year the Ilinden–Preobrazhenie Uprising, a failed rebellion organised in Macedonia by a Bulgarian secret revolutionary society, intensified the path towards war.

In a telegram dated 1 July 1914, Čolak-Antić warned Prime Minister Nikola Pašić that a loan offered by the German Empire had bound the Bulgarian government to the camp of the Triple Alliance, posing an imminent danger to Serbia.

[17] He also informed Pašić that the Bulgarians had appointed eighteen vojvodes (military commanders) to various cities in Macedonia, indicating preparations that threatened Serbian interests in the region.

Later that day, Radoslavov signed a military convention with Germany and Austria-Hungary, placing Bulgaria firmly in the camp of the Central Powers and making it an enemy of Serbia, Russia, France, and Britain, and an ally of the Ottoman Empire.

Čolak-Antić was dismayed when the British Foreign Secretary, Edward Grey, insisted on giving Bulgaria another chance, believing Bulgarian assurances of peaceful intentions towards the Allies.

On 31 October 1915, he arrived in Raška and met with representatives from France, Great Britain, Russia, and Italy, facilitating discussions aimed at reinforcing Serbia's alliances and securing urgent aid.

After spending the night in Raška, he escorted these representatives to Mitrovica for consultations with King Peter I, Prime Minister Nikola Pašić, and other government officials.

[25] Facing overwhelming enemy forces and the risk of encirclement, the Serbian government and military leadership decided to conduct a strategic retreat through the mountains of Albania towards the Adriatic Sea.

The retreat, undertaken during harsh winter conditions, resulted in significant loss of life due to severe weather, lack of resources, and disease.

Upon reaching the Albanian coast, survivors were evacuated by Allied naval forces to the island of Corfu, where the Serbian government established itself in exile, and the army underwent reorganisation.

[26] In Salonika, Čolak-Antić was involved in the trial of Colonel Dragutin Dimitrijević (Apis) and other members of the Black Hand, which addressed internal conflicts within the Serbian military and government.

During this time, Čolak-Antić undertook diplomatic missions across Europe to maintain alliances with the Entente Powers and to advocate for increased military and humanitarian support for Serbia.

[28] After returning to diplomatic duties in 1918, Čolak-Antić was appointed as the Ambassador of the newly formed Kingdom of Serbs, Croats and Slovenes to Sweden, taking up residence in Stockholm on 18 February 1918, during the final year of World War I.

[29] In December 1918, King Ferdinand of Romania sought to honour Regent Alexander of Serbia to foster closer bilateral relations and alleviate tensions in the Banat region, which was under Serbian military occupation.

[32] Earlier, on 21 September, Čolak-Antić had reached out to Miroslav Spalajković, the Serbian representative in Arkhangelsk, seeking information about Princess Jelena and her children, emphasising the king's concern for their safety.

[32] On 8 December 1920, following a budget reduction,[30] the Yugoslav Foreign Ministry closed all diplomatic representations in the Scandinavian countries,including the embassies in Sweden, Denmark, and Norway.

[3] According to historian Srđan Mićić, alongside Živojin Balugdžić and Miroslav Spalajković, he became one of the top diplomats under Regent and later King Alexander I Karađorđević.

[36] His brother, Vojin Čolak-Antić, served as the military attaché in Bucharest from July 1923 to January 1927,[5] working on resolving issues related to the tri-border area between the Kingdom of Yugoslavia, Romania, and Hungary.

[37] The collaboration between Yugoslavia and Romania during the 1920s and early 1930s peaked significantly largely due to Čolak-Antić's diplomatic dedication to fostering a productive political climate.

[38] During his time in Bucharest, Čolak-Antić maintained detailed records of his experiences and observations, which were later published in a book, providing valuable insights into the diplomatic history of the era.

[39] In July 1929, while serving as head of the Yugoslav delegation, Čolak-Antić was temporarily recalled to Belgrade to receive new instructions from Vojislav Marinković, the Minister of Foreign Affairs.

During World War I negotiations with Bulgaria in July 1915, he was described as possessing "a refined courtesy and a real impartiality which dictated all the actions of his important position during a very delicate situation.