List of Famous people with last name I

William Kissam Vanderbilt I was an American heir, businessman, philanthropist and horsebreeder. Born into the Vanderbilt family, he managed his family's railroad investments.

Wenceslas I, Duke of Saxe-Wittenberg from the House of Ascania ruled from 1370 to 1388 and was a prince-elector of the Holy Roman Empire as well as Prince of Lüneburg. He was the son of Rudolf I and his 3rd wife, Agnes of Lindow-Ruppin.

Frederick Christian I was Duke of Schleswig-Holstein-Sonderburg-Augustenburg from 1754 to 1794.

Louis I, Duke of Anjou was the second son of John II of France and Bonne of Bohemia. Born at the Château de Vincennes, Louis was the first of the Angevin branch of the French royal house. His father appointed him Count of Anjou and Count of Maine in 1356, and then raised him to the title Duke of Anjou in 1360 and Duke of Touraine in 1370.

Frederick I, the Belligerent or the Warlike, a member of the House of Wettin, ruled as Margrave of Meissen from 1407 and Elector of Saxony from 1423 until his death.

John I of Zweibrücken was Count Palatine and Duke of Zweibrücken during 1569–1604.

Radama I "the Great" (1793–1828) was the first Malagasy sovereign to be recognized as King of Madagascar (1810–1828) by a European state. He came to power at the age of 18 following the death of his father, King Andrianampoinimerina. Under Radama's rule and at his invitation, the first Europeans entered his central highland Kingdom of Imerina and its capital at Antananarivo. Radama encouraged these London Missionary Society envoys to establish schools to teach tradecraft and literacy to nobles and potential military and civil service recruits; they also introduced Christianity and taught literacy using the translated Bible. A wide range of political and social reforms were enacted under his rule, including an end to the international slave trade, which had historically been a key source of wealth and armaments for the Merina monarchy. Through aggressive military campaigns he successfully united two-thirds of the island under his rule. Abuse of alcohol weakened his health and he died prematurely at age 35. He was succeeded by his highest-ranking wife, Ranavalona I.

Al-Adil I was the fourth Sultan of Egypt and Syria, and brother of Saladin, who founded both the Sultanate of Egypt, and the Ayyubid dynasty. he was known to the Crusaders as Saphadin, a name by which he is still known in the Western world. A gifted and effective administrator and organizer, Al-Adil provided crucial military and civilian support for the great campaigns of Saladin. He was also a capable general and strategist in his own right, and was instrumental in the transformation of the decayed Fatimad Caliphate of Cairo into the Ayyubid Sultanate of Egypt.

Eleanor of Castile (1200—1244) was Queen of Aragon by her marriage to King James I of Aragon.

Theodoric I, called the Oppressed, was the Margrave of Meissen from 1198 until his death. He was the second son of Otto II, Margrave of Meissen and Hedwig of Brandenburg.