Ferdinand (1865–1927), known as "the Unifier," reigned as King of Romania from 1914 until his death. Born into the Catholic branch of the Hohenzollern royal family, he became Crown Prince of Romania in 1889. He married Princess Maria Alexandra Victoria, later Queen Marie. In 1914, he ascended the throne as Ferdinand I, ruling during World War I, siding with the Triple Entente. Romania expanded significantly after the war, becoming "Greater Romania," and Ferdinand was crowned king in 1922. His reign oversaw societal changes including agrarian reform and universal suffrage. A dynastic crisis emerged when his son, Prince Carol, renounced the throne's succession, leading to Ferdinand's removal of Carol's name from the royal house. Ferdinand passed away in 1927 due to cancer, succeeded by his grandson Michael under a regency composed of Prince Nicholas, patriarch Miron Cristea, and Gheorghe Buzdugan.

Ferdinand I of Romania - Wikipedia