Radama I (rädä´mə), c.1793–1828, founder of the kingdom of Madagascar. He succeeded (1810) his father, Andrianimpoinimerina, as king of Merina, a small kingdom on the central plateau of the island. With British aid, he trained his army along European lines and brought (1817–24) most of Madagascar under his rule. He encouraged Western learning and Christianity. His widow, Queen Ranavalona I, succeeded him. He is often called Radama the Great.