Born on April 15

68 Gaius Maecenas an ally, friend and political advisor to Octavian as well as an important patron for the new generation of Augustan poets, including both Horace and Virgil. During the reign of Augustus, Maecenas served as a quasi-culture minister to the Emperor
1282 Frederick IV Duke of Lorraine the Duke of Lorraine from 1312 to his death.
1303 Catherine of Valois (1303–1346) titular Empress of Constantinople from 1308 to her death as Catherine She was Princess consort of Achaea and Taranto, and also regent of Achaia from 1332 to 1341, and Governor of Cephalonia from 1341 to her death.
1366 Henry IV of England King of England and Lord of Ireland. He was the tenth King of England of the House of Plantagenet and also asserted his grandfather's claim to the title King of France. He was born at Bolingbroke Castle in Lincolnshire, hence his other name, Henry Bolingbroke /ˈbɒlɪŋbrʊk/. His father, John of Gaunt, was the third son of Edward III, and enjoyed a position of considerable influence during much of the reign of Henry's cousin Richard II, whom Henry eventually deposed. Henry's mother was Blanche, heiress to the considerable Lancaster estates, and thus he became the first King of England from the Lancaster branch of the Plantagenets
1452 Leonardo da Vinci an Italian polymath, painter, sculptor, architect, musician, mathematician, engineer, inventor, anatomist, geologist, cartographer, botanist, and writer. He is widely considered to be one of the greatest painters of all time and perhaps the most diversely talented person ever to have lived. His genius, perhaps more than that of any other figure, epitomized the Renaissance humanist ideal. Leonardo has often been described as the archetype of the Renaissance Man, a man of "unquenchable curiosity" and "feverishly inventive imagination". According to art historian Helen Gardner, the scope and depth of his interests were without precedent and "his mind and personality seem to us superhuman, the man himself mysterious and remote". Marco Rosci states that while there is much speculation about Leonardo, his vision of the world is essentially logical rather than mysterious, and that the empirical methods he employed were unusual for his time
1459 Filippino Lippi an Italian painter working during the High Renaissance in Florence, Italy.
1469 Guru Nanak the founder of Sikhism and the first of the Sikh Gurus. His birth is celebrated world-wide on Kartik Puranmashi, the full-moon day which falls on different dates each year in the month of Katak, October–November
1548 Pietro Cataldi an Italian mathematician. A citizen of Bologna, he taught mathematics and astronomy and also worked on military problems. His work included the development of continued fractions and a method for their representation. He was one of many mathematicians who attempted to prove Euclid's fifth postulate. Cataldi discovered the sixth and seventh primes later to acquire the designation Mersenne primes by 1588. His discovery of the 6th, that corresponding to p=17 in the formula Mp=2p-1, exploded a many-times repeated number-theoretical myth that the perfect numbers had units digits that invariably alternated between 6 and 8; and that of the 7th held the record for the largest known prime for almost two centuries, until Leonhard Euler discovered that 231 - 1 was the eighth Mersenne prime. Although Cataldi also claimed that p=23, 29, 31 and 37 all also generate Mersenne primes , his text's clear demonstration shows that he had genuinely established the fact through p=19
1563 Guru Arjan the first Sikh martyr and the fifth of the eleven Sikh Gurus, who compiled writings to create the eleventh, the living Guru, Guru Granth Sahib. He was born in Goindval, Punjab the youngest son of Guru Ram Das and Bibi Bhani, the daughter of Guru Amar Das. He was the first Sikh Guru killed by Muslims
1588 Claudius Salmasius the Latin name of Claude Saumaise , a French classical scholar.
1608 Honoré Fabri a French Jesuit theologian. He was a mathematician, physicist and controversialist
1641 Robert Sibbald a Scottish physician and antiquary.
1642 Suleiman II the Sultan of the Ottoman Empire from 1687 to 1691.
1646 Christian V of Denmark king of Denmark and Norway from 1670 until his death in 1699.
1659 Adam Ludwig Lewenhaupt a Swedish general.
1682 Jan van Huysum a Dutch painter.
1684 Catherine I of Russia the second wife of Peter I of Russia, reigned as Empress of Russia from 1725 until her death.
1688 Johann Friedrich Fasch a German violinist and composer.
1688 Johann Georg Bergmüller a painter, particularly of frescoes, of the Baroque.
1707 Leonhard Euler a pioneering Swiss mathematician and physicist. He made important discoveries in fields as diverse as infinitesimal calculus and graph theory. He also introduced much of the modern mathematical terminology and notation, particularly for mathematical analysis, such as the notion of a mathematical function. He is also renowned for his work in mechanics, fluid dynamics, optics, astronomy, and music theory
1710 William Cullen a Scottish physician, chemist and agriculturalist, and one of the most important professors at the Edinburgh Medical School, during its heyday as the leading center of medical education in the English-speaking world.
1710 Marie Anne de Cupis de Camargo a French/Belgian dancer. The first woman to execute the entrechat quatre, Camargo was also responsible for two innovations in ballet as she was the first dancer to wear slippers instead of heeled shoes, and she was the first female to wear the short calf-length ballet skirt and the now standardized ballet tights
1718 Christian Horrebow a Danish astronomer of the 18th century. He was a son of Peder Horrebow, whom he succeeded as director of the observatory associated with the University of Copenhagen
1724 Frederick IV Landgrave of Hesse-Homburg Landgrave of Hesse-Homburg.
1730 Moses Harris an English entomologist and engraver.
1741 Charles Willson Peale an American painter, soldier and naturalist. He is best remembered for his portrait paintings of leading figures of the American Revolution, as well as for establishing one of the first museums
1766 Friedrich Bouterwek born to a mining director at Oker, today a district of Goslar in Lower Saxony, and studied law and philology under Christian Gottlob Heyne and Johann Georg Heinrich Feder at the University of Göttingen.
1771 Nicolas Chopin a teacher of French language in Prussian- and Russian-ruled Poland, and father of Polish composer Frédéric Chopin.
1772 Étienne Geoffroy Saint-Hilaire a French naturalist who established the principle of "unity of composition". He was a colleague of Jean-Baptiste Lamarck and expanded and defended Lamarck's evolutionary theories. Geoffroy's scientific views had a transcendental flavor and were similar to those of German morphologists like Lorenz Oken. He believed in the underlying unity of organismal design, and the possibility of the transmutation of species in time, amassing evidence for his claims through research in comparative anatomy, paleontology, and embryology
1773 Josef August Schultes an Austrian botanist and professor from Vienna. Together with Johann Jacob Roemer , he published the 16th edition of Linnaeus' Systema Vegetabilium. In 1821, he was elected a foreign member of the Royal Swedish Academy of Sciences. He was the father of Julius Hermann Schultes
1777 Heinrich Marx a lawyer and the father of the socialist philosopher Karl Marx.
1786 Walerian Łukasiński a Polish officer and political activist. Sentenced by Russian Imperial authorities to 14 years' imprisonment, he was never released and died after 46 years, becoming a symbol of the Polish struggle for independence
1788 Semyon Ivanovich Yanovsky a Russian naval officer and chief manager of the Russian-American Company.
1789 Albert (dancer) a French ballet dancer and ballet master, under the stage name Albert.
1792 Anastasio Aquino a Salvadoran indigenous leader who led the Insurrection of the Nonualcos, a campesino uprising in El Salvador during the time it belonged to the Federal Republic of Central America.
1793 Friedrich Georg Wilhelm von Struve a German astronomer from a famous dynasty.
1795 Fulgence Fresnel a French Orientalist who was a native of Mathieu, Calvados. He was brother to physicist Augustin Fresnel
1797 Adolphe Thiers a French politician and historian. He was a leading historian of the French Revolution, with a multivolume history that argued that the republicanism of the Revolution was the central theme of modern French history
1800 James Clark Ross a British naval officer and explorer remembered today for his exploration of the Arctic with his uncle Sir John Ross and Sir William Parry and, in particular, his own expedition to Antarctica.
1800 Gilbert Thomas Burnett a British botanist.
1804 François-Napoléon-Marie Moigno a French Catholic priest and one time Jesuit, as well as a physicist and author. He considered himself a student of Cauchy
1806 Samuel Rayner an English landscape artist, known for his paintings of buildings and their interiors, including abbeys, churches and old mansions. He achieved the distinction of having a work accepted for exhibition at the Royal Academy at only 15 years of age. His wife, Ann Rayner, was an engraver on Ashford Black Marble and six of their children went on to be professional artists
1806 Émile Souvestre a French novelist who was a native of Morlaix, Finistère.
1809 Hermann Grassmann a German polymath, renowned in his day as a linguist and now also admired as a mathematician. He was also a physicist, neohumanist, general scholar, and publisher. His mathematical work was little noted until he was in his sixties
1812 Théodore Rousseau Étienne Pierre Théodore Rousseau , French painter of the Barbizon school.
1813 Theodor Kotschy an Austrian botanist and explorer who was a native of Ustroń, in Austrian Silesia. He was the son of theologian Carl Friedrich Kotschy
1814 Adalbert Schnizlein a German botanist and pharmacist. He is largely remembered for his work in the fields of plant taxonomy and phytogeography
1819 Karl Langer an Austrian anatomist. He is known for his work in the field of topographical anatomy
1821 Catesby ap Roger Jones an officer in the U.S. Navy who became a commander in the Confederate Navy during the American Civil War. He assumed command of CSS Virginia during the Battle of Hampton Roads and engaged the USS Monitor in that world famous battle of the two iron clads
1824 Aniceto Arce President of Bolivia from 1888 until 1892. The Aniceto Arce Province is named after him. Arce was a native of Tarija but was educated as a lawyer and resided most of his life in Sucre, where he became one of the country's foremost silver-mining tycoons. A supporter of Linares and Constitutionalist government, he later served in Congress during the 1870s until the time of the Daza dictatorship