Horace Mann was an American educational reformer born in 1796. He is often called the "Father of the American Public School System" for his efforts to promote universal public education. Mann believed that education was essential for a democratic society and worked to improve schools, teacher training, and educational standards. Mann served as the first Secretary of the Massachusetts Board of Education, where he advocated for free public schools and better funding. His ideas influenced the establishment of public education systems across the United States, making education more accessible to all children, regardless of their background or social status.