Florian Cajori (1859‒1930) was an eminent Swiss-American mathematician who wrote several books on the history of Mathematics. His work A History of Mathematics (here presented in the second edition, revised and enlarged) was the first to present the topic in a readable fashion for the general public in the United States.
It remains today a prominent and complete historical masterpiece. Cajori is considered the founding father of the History of Mathematics as an academic discipline. Indeed he was the first to be appointed as professor in History of Mathematics at the University of Berkeley, California, which was the first chair on this subject created in the United States.
He held the chair in Berkeley until his death in 1930 and is still one of the most cited and quoted historians of mathematics of all time.