Konge af Montenegro 1910-18. Erklærede Tyrkiet krig i 1912 og erobrede Shkodër i Albanien. Måtte efter østrigsk pres opgive byen igen.
Prina (1860–1910) og konge (1910–18) af Montene-gro, efterfulgte sin onkel Danilo II. I 1862 blev Nicholas, efter en række grænsetræfninger, tvunget i krig mod Det osmanniske Rige. Trods heroisk modstand måtte han indgå en ugundstig fredsaftale . Derpå reorganiserede han sin hær .
Although he rivaled Serbia for leadership of the South Slavs, in 1876 he allied himself with Serbia, intervened in favor of the rebels in Bosnia and Herzegovina, declared war on the Ottomans, and waged a successful campaign in Herzegovina. Russia’s entrance (1877) into the war assured him of success. The Treaty of San Stefano (1878) trebled the size of Montenegro; the final boundaries adopted at the Congress of Berlin reduced the Montenegrin gains but gave access to the Adriatic Sea. Montenegro was recognized as fully independent, and, in 1910, Nicholas proclaimed himself king. He sided with Serbia in World War I but sought (1915) a separate peace with the Central Powers after his troops had been routed. When Montenegro was occupied by Austrian troops, he fled the country. In exile, he resisted the proposed union of Montenegro with Serbia under a Serbian king and as a result was deposed (1918) by a national assembly, which proclaimed the union. Nicholas succeeded in marrying his five daughters into the ruling houses of Europe, including those of Italy, Russia, and Serbia.