Stephen Vladislav I was a Serbian king who reigned from 1234 to 1243. A member of the Nemanjić dynasty, he ascended to the throne after his elder brother, Radoslav, was deposed by the nobility due to foreign influence. During his rule, he strengthened Serbia's position by marrying the daughter of the Bulgarian ruler Ivan Asen II and defending the province of Hum against Hungarian crusaders. He eventually abdicated in favor of his younger brother, though he continued to serve as the governor of Zeta until his death in 1267.